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diff --git a/tools/bug_tool/ClientForm.py b/tools/bug_tool/ClientForm.py
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+"""HTML form handling for web clients.
+
+ClientForm is a Python module for handling HTML forms on the client
+side, useful for parsing HTML forms, filling them in and returning the
+completed forms to the server.  It has developed from a port of Gisle
+Aas' Perl module HTML::Form, from the libwww-perl library, but the
+interface is not the same.
+
+The most useful docstring is the one for HTMLForm.
+
+RFC 1866: HTML 2.0
+RFC 1867: Form-based File Upload in HTML
+RFC 2388: Returning Values from Forms: multipart/form-data
+HTML 3.2 Specification, W3C Recommendation 14 January 1997 (for ISINDEX)
+HTML 4.01 Specification, W3C Recommendation 24 December 1999
+
+
+Copyright 2002-2003 John J. Lee <jjl@pobox.com>
+Copyright 1998-2000 Gisle Aas.
+
+This code is free software; you can redistribute it and/or modify it
+under the terms of the BSD License (see the file COPYING included with
+the distribution).
+
+"""
+
+# XXX
+# Treat unknown controls as text controls? (this was a recent LWP
+#  HTML::Form change)  I guess this is INPUT with no TYPE?  Check LWP
+#  source and browser behaviour.
+# Support for list item ids.  How to handle missing ids? (How do I deal
+#  with duplicate OPTION labels ATM?  Can't remember...)
+# Arrange things so can automatically PyPI-register with categories
+#  without messing up 1.5.2 compatibility.
+# Tests need work.
+# Test single and multiple file upload some more on the web.
+# Does file upload work when name is missing?  Sourceforge tracker form
+#  doesn't like it.  Check standards, and test with Apache.  Test binary
+#  upload with Apache.
+# Add label support for CHECKBOX and RADIO.
+# Better docs.
+# Deal with character sets properly.  Not sure what the issues are here.
+#  I don't *think* any encoding of control names, filenames or data is
+#   necessary -- HTML spec. doesn't require it, and Mozilla Firebird 0.6
+#   doesn't seem to do it.
+#  Add charset parameter to Content-type headers?  How to find value??
+# Get rid of MapBase, AList and MimeWriter.
+# I'm not going to fix this unless somebody tells me what real servers
+#  that want this encoding actually expect: If enctype is
+#  application/x-www-form-urlencoded and there's a FILE control present.
+#  Strictly, it should be 'name=data' (see HTML 4.01 spec., section
+#  17.13.2), but I send "name=" ATM.  What about multiple file upload??
+# Get rid of the two type-switches (for kind and click*).
+# Remove single-selection code: can be special case of multi-selection,
+#  with a few variations, I think.
+# Factor out multiple-selection list code?  May not be easy.  Maybe like
+#  this:
+
+#         ListControl
+#             ^
+#             |       MultipleListControlMixin
+#             |             ^
+#        SelectControl     /
+#             ^           /
+#              \         /
+#          MultiSelectControl
+
+
+# Plan
+# ----
+# Maybe a 0.2.x, cleaned up a bit and with id support for list items?
+#  Not sure it's worth it, really.
+#   Remove toggle methods.
+#   Replace by_label with choice between value / id / label /
+#    element contents (see discussion with Gisle about labels on
+#    libwww-perl list).
+#   ...what else?
+# Work on DOMForm.
+# XForms?  Don't know if there's a need here.
+
+
+try: True
+except NameError:
+    True = 1
+    False = 0
+
+try: bool
+except NameError:
+    def bool(expr):
+        if expr: return True
+        else: return False
+
+import sys, urllib, urllib2, types, string, mimetools, copy
+from urlparse import urljoin
+from cStringIO import StringIO
+try:
+    import UnicodeType
+except ImportError:
+    UNICODE = False
+else:
+    UNICODE = True
+
+VERSION = "0.1.13"
+
+CHUNK = 1024  # size of chunks fed to parser, in bytes
+
+# This version of urlencode is from my Python 1.5.2 back-port of the
+# Python 2.1 CVS maintenance branch of urllib.  It will accept a sequence
+# of pairs instead of a mapping -- the 2.0 version only accepts a mapping.
+def urlencode(query,doseq=False,):
+    """Encode a sequence of two-element tuples or dictionary into a URL query \
+string.
+
+    If any values in the query arg are sequences and doseq is true, each
+    sequence element is converted to a separate parameter.
+
+    If the query arg is a sequence of two-element tuples, the order of the
+    parameters in the output will match the order of parameters in the
+    input.
+    """
+
+    if hasattr(query,"items"):
+        # mapping objects
+        query = query.items()
+    else:
+        # it's a bother at times that strings and string-like objects are
+        # sequences...
+        try:
+            # non-sequence items should not work with len()
+            x = len(query)
+            # non-empty strings will fail this
+            if len(query) and type(query[0]) != types.TupleType:
+                raise TypeError()
+            # zero-length sequences of all types will get here and succeed,
+            # but that's a minor nit - since the original implementation
+            # allowed empty dicts that type of behavior probably should be
+            # preserved for consistency
+        except TypeError:
+            ty,va,tb = sys.exc_info()
+            raise TypeError("not a valid non-string sequence or mapping "
+                            "object", tb)
+
+    l = []
+    if not doseq:
+        # preserve old behavior
+        for k, v in query:
+            k = urllib.quote_plus(str(k))
+            v = urllib.quote_plus(str(v))
+            l.append(k + '=' + v)
+    else:
+        for k, v in query:
+            k = urllib.quote_plus(str(k))
+            if type(v) == types.StringType:
+                v = urllib.quote_plus(v)
+                l.append(k + '=' + v)
+            elif UNICODE and type(v) == types.UnicodeType:
+                # is there a reasonable way to convert to ASCII?
+                # encode generates a string, but "replace" or "ignore"
+                # lose information and "strict" can raise UnicodeError
+                v = urllib.quote_plus(v.encode("ASCII","replace"))
+                l.append(k + '=' + v)
+            else:
+                try:
+                    # is this a sufficient test for sequence-ness?
+                    x = len(v)
+                except TypeError:
+                    # not a sequence
+                    v = urllib.quote_plus(str(v))
+                    l.append(k + '=' + v)
+                else:
+                    # loop over the sequence
+                    for elt in v:
+                        l.append(k + '=' + urllib.quote_plus(str(elt)))
+    return string.join(l, '&')
+
+def startswith(string, initial):
+    if len(initial) > len(string): return False
+    return string[:len(initial)] == initial
+
+def issequence(x):
+    try:
+        x[0]
+    except (TypeError, KeyError):
+        return False
+    except IndexError:
+        pass
+    return True
+
+def isstringlike(x):
+    try: x+""
+    except: return False
+    else: return True
+
+
+# XXX don't really want to drag this along (MapBase, AList, MimeWriter)
+
+class MapBase:
+    """Mapping designed to be easily derived from.
+
+    Subclass it and override __init__, __setitem__, __getitem__, __delitem__
+    and keys.  Nothing else should need to be overridden, unlike UserDict.
+    This significantly simplifies dictionary-like classes.
+
+    Also different from UserDict in that it has a redonly flag, and can be
+    updated (and initialised) with a sequence of pairs (key, value).
+
+    """
+    def __init__(self, init=None):
+        self._data = {}
+        self.readonly = False
+        if init is not None: self.update(init)
+
+    def __getitem__(self, key):
+        return self._data[key]
+
+    def __setitem__(self, key, item):
+        if not self.readonly:
+            self._data[key] = item
+        else:
+            raise TypeError("object doesn't support item assignment")
+
+    def __delitem__(self, key):
+        if not self.readonly:
+            del self._data[key]
+        else:
+            raise TypeError("object doesn't support item deletion")
+
+    def keys(self):
+        return self._data.keys()
+
+    # now the internal workings, there should be no need to override these:
+
+    def clear(self):
+        for k in self.keys():
+            del self[k]
+
+    def __repr__(self):
+        rep = []
+        for k, v in self.items():
+            rep.append("%s: %s" % (repr(k), repr(v)))
+        return self.__class__.__name__+"{"+(string.join(rep, ", "))+"}"
+
+    def copy(self):
+        return copy.copy(self)
+
+    def __cmp__(self, dict):
+        # note: return value is *not* boolean
+        for k, v in self.items():
+            if not (dict.has_key(k) and dict[k] == v):
+                return 1  # different
+        return 0  # the same
+
+    def __len__(self):
+        return len(self.keys())
+
+    def values(self):
+        r = []
+        for k in self.keys():
+            r.append(self[k])
+        return r
+
+    def items(self):
+        keys = self.keys()
+        vals = self.values()
+        r = []
+        for i in len(self):
+            r.append((keys[i], vals[i]))
+        return r
+
+    def has_key(self, key):
+        return key in self.keys()
+
+    def update(self, map):
+        if issequence(map) and not isstringlike(map):
+            items = map
+        else:
+            items = map.items()
+        for tup in items:
+            if not isinstance(tup, TupleType):
+                raise TypeError(
+                    "MapBase.update requires a map or a sequence of pairs")
+            k, v = tup
+            self[k] = v
+
+    def get(self, key, failobj=None):
+        if key in self.keys():
+            return self[key]
+        else:
+            return failobj
+
+    def setdefault(self, key, failobj=None):
+        if not self.has_key(key):
+            self[key] = failobj
+        return self[key]
+
+
+class AList(MapBase):
+    """Read-only ordered mapping."""
+    def __init__(self, seq=[]):
+        self.readonly = True
+        self._inverted = False
+        self._data = list(seq[:])
+        self._keys = []
+        self._values = []
+        for key, value in seq:
+            self._keys.append(key)
+            self._values.append(value)
+
+    def set_inverted(self, inverted):
+        if (inverted and not self._inverted) or (
+            not inverted and self._inverted):
+            self._keys, self._values = self._values, self._keys
+        if inverted: self._inverted = True
+        else: self._inverted = False
+
+    def __getitem__(self, key):
+        try:
+            i = self._keys.index(key)
+        except ValueError:
+            raise KeyError(key)
+        return self._values[i]
+
+    def __delitem__(self, key):
+        try:
+            i = self._keys.index[key]
+        except ValueError:
+            raise KeyError(key)
+        del self._values[i]
+
+    def keys(self): return list(self._keys[:])
+    def values(self): return list(self._values[:])
+    def items(self):
+        data = self._data[:]
+        if not self._inverted:
+            return data
+        else:
+            newdata = []
+            for k, v in data:
+                newdata.append((v, k))
+            return newdata
+
+
+# This cut-n-pasted MimeWriter from standard library is here so can add
+# to HTTP headers rather than message body when appropriate.  It also uses
+# \r\n in place of \n.  This is nasty.
+class MimeWriter:
+
+    """Generic MIME writer.
+
+    Methods:
+
+    __init__()
+    addheader()
+    flushheaders()
+    startbody()
+    startmultipartbody()
+    nextpart()
+    lastpart()
+
+    A MIME writer is much more primitive than a MIME parser.  It
+    doesn't seek around on the output file, and it doesn't use large
+    amounts of buffer space, so you have to write the parts in the
+    order they should occur on the output file.  It does buffer the
+    headers you add, allowing you to rearrange their order.
+
+    General usage is:
+
+    f = <open the output file>
+    w = MimeWriter(f)
+    ...call w.addheader(key, value) 0 or more times...
+
+    followed by either:
+
+    f = w.startbody(content_type)
+    ...call f.write(data) for body data...
+
+    or:
+
+    w.startmultipartbody(subtype)
+    for each part:
+        subwriter = w.nextpart()
+        ...use the subwriter's methods to create the subpart...
+    w.lastpart()
+
+    The subwriter is another MimeWriter instance, and should be
+    treated in the same way as the toplevel MimeWriter.  This way,
+    writing recursive body parts is easy.
+
+    Warning: don't forget to call lastpart()!
+
+    XXX There should be more state so calls made in the wrong order
+    are detected.
+
+    Some special cases:
+
+    - startbody() just returns the file passed to the constructor;
+      but don't use this knowledge, as it may be changed.
+
+    - startmultipartbody() actually returns a file as well;
+      this can be used to write the initial 'if you can read this your
+      mailer is not MIME-aware' message.
+
+    - If you call flushheaders(), the headers accumulated so far are
+      written out (and forgotten); this is useful if you don't need a
+      body part at all, e.g. for a subpart of type message/rfc822
+      that's (mis)used to store some header-like information.
+
+    - Passing a keyword argument 'prefix=<flag>' to addheader(),
+      start*body() affects where the header is inserted; 0 means
+      append at the end, 1 means insert at the start; default is
+      append for addheader(), but insert for start*body(), which use
+      it to determine where the Content-type header goes.
+
+    """
+
+    def __init__(self, fp, http_hdrs=None):
+        self._http_hdrs = http_hdrs
+        self._fp = fp
+        self._headers = []
+        self._boundary = []
+        self._first_part = True
+
+    def addheader(self, key, value, prefix=0,
+                  add_to_http_hdrs=0):
+        """
+        prefix is ignored if add_to_http_hdrs is true.
+        """
+        lines = string.split(value, "\r\n")
+        while lines and not lines[-1]: del lines[-1]
+        while lines and not lines[0]: del lines[0]
+        if add_to_http_hdrs:
+            value = string.join(lines, "")
+            self._http_hdrs.append((key, value))
+        else:
+            for i in range(1, len(lines)):
+                lines[i] = "    " + string.strip(lines[i])
+            value = string.join(lines, "\r\n") + "\r\n"
+            line = key + ": " + value
+            if prefix:
+                self._headers.insert(0, line)
+            else:
+                self._headers.append(line)
+
+    def flushheaders(self):
+        self._fp.writelines(self._headers)
+        self._headers = []
+
+    def startbody(self, ctype=None, plist=[], prefix=1,
+                  add_to_http_hdrs=0, content_type=1):
+        """
+        prefix is ignored if add_to_http_hdrs is true.
+        """
+        if content_type and ctype:
+            for name, value in plist:
+                ctype = ctype + ';\r\n %s=\"%s\"' % (name, value)
+            self.addheader("Content-type", ctype, prefix=prefix,
+                           add_to_http_hdrs=add_to_http_hdrs)
+        self.flushheaders()
+        if not add_to_http_hdrs: self._fp.write("\r\n")
+        self._first_part = True
+        return self._fp
+
+    def startmultipartbody(self, subtype, boundary=None, plist=[], prefix=1,
+                           add_to_http_hdrs=0, content_type=1):
+        boundary = boundary or mimetools.choose_boundary()
+        self._boundary.append(boundary)
+        return self.startbody("multipart/" + subtype,
+                              [("boundary", boundary)] + plist,
+                              prefix=prefix,
+                              add_to_http_hdrs=add_to_http_hdrs,
+                              content_type=content_type)
+
+    def nextpart(self):
+        boundary = self._boundary[-1]
+        if self._first_part:
+            self._first_part = False
+        else:
+            self._fp.write("\r\n")
+        self._fp.write("--" + boundary + "\r\n")
+        return self.__class__(self._fp)
+
+    def lastpart(self):
+        if self._first_part:
+            self.nextpart()
+        boundary = self._boundary.pop()
+        self._fp.write("\r\n--" + boundary + "--\r\n")
+
+
+class ControlNotFoundError(ValueError): pass
+class ItemNotFoundError(ValueError): pass
+class ItemCountError(ValueError): pass
+
+class ParseError(Exception): pass
+
+
+def ParseResponse(response, select_default=False, ignore_errors=False):
+    """Parse HTTP response and return a list of HTMLForm instances.
+
+    The return value of urllib2.urlopen can be conveniently passed to this
+    function as the response parameter.
+
+    ClientForm.ParseError is raised on parse errors.
+
+    response: file-like object (supporting read() method) with a method
+     geturl(), returning the base URI of the HTTP response
+    select_default: for multiple-selection SELECT controls and RADIO controls,
+     pick the first item as the default if none are selected in the HTML
+    ignore_errors: don't raise ParseError, and carry on regardless if the
+     parser gets confused
+
+    Pass a true value for select_default if you want the behaviour specified by
+    RFC 1866 (the HTML 2.0 standard), which is to select the first item in a
+    RADIO or multiple-selection SELECT control if none were selected in the
+    HTML.  Most browsers (including Microsoft Internet Explorer (IE) and
+    Netscape Navigator) instead leave all items unselected in these cases.  The
+    W3C HTML 4.0 standard leaves this behaviour undefined in the case of
+    multiple-selection SELECT controls, but insists that at least one RADIO
+    button should be checked at all times, in contradiction to browser
+    behaviour.
+
+    Precisely what ignore_errors does isn't well-defined yet, so don't rely too
+    much on the current behaviour -- if you want robustness, you're better off
+    fixing the HTML before passing it to this function.
+
+    """
+    return ParseFile(response, response.geturl(), select_default)
+
+def ParseFile(file, base_uri, select_default=False, ignore_errors=False):
+    """Parse HTML and return a list of HTMLForm instances.
+
+    ClientForm.ParseError is raised on parse errors.
+
+    file: file-like object (supporting read() method) containing HTML with zero
+     or more forms to be parsed
+    base_uri: the base URI of the document
+
+    For the other arguments and further details, see ParseResponse.__doc__.
+
+    """
+    fp = _FORM_PARSER_CLASS(ignore_errors)
+    while 1:
+        data = file.read(CHUNK)
+        fp.feed(data)
+        if len(data) != CHUNK: break
+    forms = []
+    for (name, action, method, enctype), attrs, controls in fp.forms:
+        if action is None:
+            action = base_uri
+        else:
+            action = urljoin(base_uri, action)
+        form = HTMLForm(action, method, enctype, name, attrs)
+        for type, name, attr in controls:
+            form.new_control(type, name, attr, select_default=select_default)
+        forms.append(form)
+    for form in forms:
+        form.fixup()
+    return forms
+
+
+class _AbstractFormParser:
+    """forms attribute contains HTMLForm instances on completion."""
+    # pinched (and modified) from Moshe Zadka
+    def __init__(self, ignore_errors, entitydefs=None):
+        if entitydefs is not None:
+            self.entitydefs = entitydefs
+        self._ignore_errors = ignore_errors
+        self.forms = []
+        self._current_form = None
+        self._select = None
+        self._optgroup = None
+        self._option = None
+        self._textarea = None
+
+    def error(self, error):
+        if not self._ignore_errors: raise error
+
+    def start_form(self, attrs):
+        if self._current_form is not None:
+            self.error(ParseError("nested FORMs"))
+        name = None
+        action = None
+        enctype = "application/x-www-form-urlencoded"
+        method = "GET"
+        d = {}
+        for key, value in attrs:
+            if key == "name":
+                name = value
+            elif key == "action":
+                action = value
+            elif key == "method":
+                method = string.upper(value)
+            elif key == "enctype":
+                enctype = string.lower(value)
+            else:
+                d[key] = value
+        controls = []
+        self._current_form = (name, action, method, enctype), d, controls
+
+    def end_form(self):
+        if self._current_form is None:
+            self.error(ParseError("end of FORM before start"))
+        self.forms.append(self._current_form)
+        self._current_form = None
+
+    def start_select(self, attrs):
+        if self._current_form is None:
+            self.error(ParseError("start of SELECT before start of FORM"))
+        if self._select is not None:
+            self.error(ParseError("nested SELECTs"))
+        if self._textarea is not None:
+            self.error(ParseError("SELECT inside TEXTAREA"))
+        d = {}
+        for key, val in attrs:
+            d[key] = val
+
+        self._select = d
+
+        self._append_select_control({"__select": d})
+
+    def end_select(self):
+        if self._current_form is None:
+            self.error(ParseError("end of SELECT before start of FORM"))
+        if self._select is None:
+            self.error(ParseError("end of SELECT before start"))
+
+        if self._option is not None:
+            self._end_option()
+
+        self._select = None
+
+    def start_optgroup(self, attrs):
+        if self._select is None:
+            self.error(ParseError("OPTGROUP outside of SELECT"))
+        d = {}
+        for key, val in attrs:
+            d[key] = val
+
+        self._optgroup = d
+
+    def end_optgroup(self):
+        if self._optgroup is None:
+            self.error(ParseError("end of OPTGROUP before start"))
+        self._optgroup = None
+
+    def _start_option(self, attrs):
+        if self._select is None:
+            self.error(ParseError("OPTION outside of SELECT"))
+        if self._option is not None:
+            self._end_option()
+
+        d = {}
+        for key, val in attrs:
+            d[key] = val
+
+        self._option = {}
+        self._option.update(d)
+        if (self._optgroup and self._optgroup.has_key("disabled") and
+            not self._option.has_key("disabled")):
+            self._option["disabled"] = None
+
+    def _end_option(self):
+        if self._option is None:
+            self.error(ParseError("end of OPTION before start"))
+
+        contents = string.strip(self._option.get("contents", ""))
+        #contents = string.strip(self._option["contents"])
+        self._option["contents"] = contents
+        if not self._option.has_key("value"):
+            self._option["value"] = contents
+        if not self._option.has_key("label"):
+            self._option["label"] = contents
+        # stuff dict of SELECT HTML attrs into a special private key
+        #  (gets deleted again later)
+        self._option["__select"] = self._select
+        self._append_select_control(self._option)
+        self._option = None
+
+    def _append_select_control(self, attrs):
+        controls = self._current_form[2]
+        name = self._select.get("name")
+        controls.append(("select", name, attrs))
+
+##     def do_option(self, attrs):
+##         if self._select is None:
+##             self.error(ParseError("OPTION outside of SELECT"))
+##         d = {}
+##         for key, val in attrs:
+##             d[key] = val
+
+##         self._option = {}
+##         self._option.update(d)
+##         if (self._optgroup and self._optgroup.has_key("disabled") and
+##             not self._option.has_key("disabled")):
+##             self._option["disabled"] = None
+
+    def start_textarea(self, attrs):
+        if self._current_form is None:
+            self.error(ParseError("start of TEXTAREA before start of FORM"))
+        if self._textarea is not None:
+            self.error(ParseError("nested TEXTAREAs"))
+        if self._select is not None:
+            self.error(ParseError("TEXTAREA inside SELECT"))
+        d = {}
+        for key, val in attrs:
+            d[key] = val
+
+        self._textarea = d
+
+    def end_textarea(self):
+        if self._current_form is None:
+            self.error(ParseError("end of TEXTAREA before start of FORM"))
+        if self._textarea is None:
+            self.error(ParseError("end of TEXTAREA before start"))
+        controls = self._current_form[2]
+        name = self._textarea.get("name")
+        controls.append(("textarea", name, self._textarea))
+        self._textarea = None
+
+    def handle_data(self, data):
+        if self._option is not None:
+            # self._option is a dictionary of the OPTION element's HTML
+            # attributes, but it has two special keys, one of which is the
+            # special "contents" key contains text between OPTION tags (the
+            # other is the "__select" key: see the end_option method)
+            map = self._option
+            key = "contents"
+        elif self._textarea is not None:
+            map = self._textarea
+            key = "value"
+        else:
+            return
+
+        if not map.has_key(key):
+            map[key] = data
+        else:
+            map[key] = map[key] + data
+
+##     def handle_data(self, data):
+##         if self._option is not None:
+##             contents = string.strip(data)
+##             controls = self._current_form[2]
+##             if not self._option.has_key("value"):
+##                 self._option["value"] = contents
+##             if not self._option.has_key("label"):
+##                 self._option["label"] = contents
+##             # self._option is a dictionary of the OPTION element's HTML
+##             # attributes, but it has two special keys:
+##             #  1. special "contents" key contains text between OPTION tags
+##             self._option["contents"] = contents
+##             #  2. stuff dict of SELECT HTML attrs into a special private key
+##             #     (gets deleted again later)
+##             self._option["__select"] = self._select
+##             self._append_select_control(self._option)
+##             self._option = None
+##         elif self._textarea is not None:
+##             #self._textarea["value"] = data
+##             if self._textarea.get("value") is None:
+##                 self._textarea["value"] = data
+##             else:
+##                 self._textarea["value"] = self._textarea["value"] + data
+
+    def do_button(self, attrs):
+        if self._current_form is None:
+            self.error(ParseError("start of BUTTON before start of FORM"))
+        d = {}
+        d["type"] = "submit"  # default
+        for key, val in attrs:
+            d[key] = val
+        controls = self._current_form[2]
+
+        type = d["type"]
+        name = d.get("name")
+        # we don't want to lose information, so use a type string that
+        # doesn't clash with INPUT TYPE={SUBMIT,RESET,BUTTON}
+        # eg. type for BUTTON/RESET is "resetbutton"
+        #     (type for INPUT/RESET is "reset")
+        type = type+"button"
+        controls.append((type, name, d))
+
+    def do_input(self, attrs):
+        if self._current_form is None:
+            self.error(ParseError("start of INPUT before start of FORM"))
+        d = {}
+        d["type"] = "text"  # default
+        for key, val in attrs:
+            d[key] = val
+        controls = self._current_form[2]
+
+        type = d["type"]
+        name = d.get("name")
+        controls.append((type, name, d))
+
+    def do_isindex(self, attrs):
+        if self._current_form is None:
+            self.error(ParseError("start of ISINDEX before start of FORM"))
+        d = {}
+        for key, val in attrs:
+            d[key] = val
+        controls = self._current_form[2]
+
+        # isindex doesn't have type or name HTML attributes
+        controls.append(("isindex", None, d))
+
+# use HTMLParser if we have it (it does XHTML), htmllib otherwise
+try:
+    import HTMLParser
+except ImportError:
+    import htmllib, formatter
+    class _FormParser(_AbstractFormParser, htmllib.HTMLParser):
+        # This is still here for compatibility with Python 1.5.2.
+        # It doesn't do the right thing with XHTML.
+        def __init__(self, ignore_errors, entitydefs=None):
+            htmllib.HTMLParser.__init__(self, formatter.NullFormatter())
+            _AbstractFormParser.__init__(self, ignore_errors, entitydefs)
+
+        def do_option(self, attrs):
+            _AbstractFormParser._start_option(self, attrs)
+
+    _FORM_PARSER_CLASS = _FormParser
+else:
+    class _XHTMLCompatibleFormParser(_AbstractFormParser, HTMLParser.HTMLParser):
+        # thanks to Michael Howitz for this!
+        def __init__(self, ignore_errors, entitydefs=None):
+            HTMLParser.HTMLParser.__init__(self)
+            _AbstractFormParser.__init__(self, ignore_errors, entitydefs)
+
+        def start_option(self, attrs):
+            _AbstractFormParser._start_option(self, attrs)
+
+        def end_option(self):
+            _AbstractFormParser._end_option(self)
+
+        def handle_starttag(self, tag, attrs):
+            try:
+                method = getattr(self, 'start_' + tag)
+            except AttributeError:
+                try:
+                    method = getattr(self, 'do_' + tag)
+                except AttributeError:
+                    pass # unknown tag
+                else:
+                    method(attrs)
+            else:
+                method(attrs)
+
+        def handle_endtag(self, tag):
+            try:
+                method = getattr(self, 'end_' + tag)
+            except AttributeError:
+                pass # unknown tag
+            else:
+                method()
+
+        # handle_charref, handle_entityref and default entitydefs are taken
+        # from sgmllib
+        def handle_charref(self, name):
+            try:
+                n = int(name)
+            except ValueError:
+                self.unknown_charref(name)
+                return
+            if not 0 <= n <= 255:
+                self.unknown_charref(name)
+                return
+            self.handle_data(chr(n))
+
+        # Definition of entities -- derived classes may override
+        entitydefs = \
+                {'lt': '<', 'gt': '>', 'amp': '&', 'quot': '"', 'apos': '\''}
+
+        def handle_entityref(self, name):
+            table = self.entitydefs
+            if name in table:
+                self.handle_data(table[name])
+            else:
+                self.unknown_entityref(name)
+                return
+
+        # These methods would have passed through the ref intact if I'd thought
+        # of it earlier, but since the old parser silently swallows unknown
+        # refs, so does this new parser.
+        def unknown_entityref(self, ref): pass
+        def unknown_charref(self, ref): pass
+
+    _FORM_PARSER_CLASS = _XHTMLCompatibleFormParser
+
+
+class Control:
+    """An HTML form control.
+
+    An HTMLForm contains a sequence of Controls.  HTMLForm delegates lots of
+    things to Control objects, and most of Control's methods are, in effect,
+    documented by the HTMLForm docstrings.
+
+    The Controls in an HTMLForm can be got at via the HTMLForm.find_control
+    method or the HTMLForm.controls attribute.
+
+    Control instances are usually constructed using the ParseFile /
+    ParseResponse functions, so you can probably ignore the rest of this
+    paragraph.  A Control is only properly initialised after the fixup method
+    has been called.  In fact, this is only strictly necessary for ListControl
+    instances.  This is necessary because ListControls are built up from
+    ListControls each containing only a single item, and their initial value(s)
+    can only be known after the sequence is complete.
+
+    The types and values that are acceptable for assignment to the value
+    attribute are defined by subclasses.
+
+    If the disabled attribute is true, this represents the state typically
+    represented by browsers by `greying out' a control.  If the disabled
+    attribute is true, the Control will raise AttributeError if an attempt is
+    made to change its value.  In addition, the control will not be considered
+    `successful' as defined by the W3C HTML 4 standard -- ie. it will
+    contribute no data to the return value of the HTMLForm.click* methods.  To
+    enable a control, set the disabled attribute to a false value.
+
+    If the readonly attribute is true, the Control will raise AttributeError if
+    an attempt is made to change its value.  To make a control writable, set
+    the readonly attribute to a false value.
+
+    All controls have the disabled and readonly attributes, not only those that
+    may have the HTML attributes of the same names.
+
+    On assignment to the value attribute, the following exceptions are raised:
+    TypeError, AttributeError (if the value attribute should not be assigned
+    to, because the control is disabled, for example) and ValueError.
+
+    If the name or value attributes are None, or the value is an empty list, or
+    if the control is disabled, the control is not successful.
+
+    Public attributes:
+
+    type: string describing type of control (see the keys of the
+     HTMLForm.type2class dictionary for the allowable values) (readonly)
+    name: name of control (readonly)
+    value: current value of control (subclasses may allow a single value, a
+     sequence of values, or either)
+    disabled: disabled state
+    readonly: readonly state
+    id: value of id HTML attribute
+
+    """
+    def __init__(self, type, name, attrs):
+        """
+        type: string describing type of control (see the keys of the
+         HTMLForm.type2class dictionary for the allowable values)
+        name: control name
+        attrs: HTML attributes of control's HTML element
+
+        """
+        raise NotImplementedError()
+
+    def add_to_form(self, form):
+        form.controls.append(self)
+
+    def fixup(self):
+        pass
+
+    def __getattr__(self, name): raise NotImplementedError()
+    def __setattr__(self, name, value): raise NotImplementedError()
+
+    def pairs(self):
+        """Return list of (key, value) pairs suitable for passing to urlencode.
+        """
+        raise NotImplementedError()
+
+    def _write_mime_data(self, mw):
+        """Write data for this control to a MimeWriter."""
+        # called by HTMLForm
+        for name, value in self.pairs():
+            mw2 = mw.nextpart()
+            mw2.addheader("Content-disposition",
+                          'form-data; name="%s"' % name, 1)
+            f = mw2.startbody(prefix=0)
+            f.write(value)
+
+    def __str__(self):
+        raise NotImplementedError()
+
+
+#---------------------------------------------------
+class ScalarControl(Control):
+    """Control whose value is not restricted to one of a prescribed set.
+
+    Some ScalarControls don't accept any value attribute.  Otherwise, takes a
+    single value, which must be string-like.
+
+    Additional read-only public attribute:
+
+    attrs: dictionary mapping the names of original HTML attributes of the
+     control to their values
+
+    """
+    def __init__(self, type, name, attrs):
+        self.__dict__["type"] = string.lower(type)
+        self.__dict__["name"] = name
+        self._value = attrs.get("value")
+        self.disabled = attrs.has_key("disabled")
+        self.readonly = attrs.has_key("readonly")
+        self.id = attrs.get("id")
+
+        self.attrs = attrs.copy()
+
+        self._clicked = False
+
+    def __getattr__(self, name):
+        if name == "value":
+            return self.__dict__["_value"]
+        else:
+            raise AttributeError("%s instance has no attribute '%s'" %
+                                 (self.__class__.__name__, name))
+
+    def __setattr__(self, name, value):
+        if name == "value":
+            if not isstringlike(value):
+                raise TypeError("must assign a string")
+            elif self.readonly:
+                raise AttributeError("control '%s' is readonly" % self.name)
+            elif self.disabled:
+                raise AttributeError("control '%s' is disabled" % self.name)
+            self.__dict__["_value"] = value
+        elif name in ("name", "type"):
+            raise AttributeError("%s attribute is readonly" % name)
+        else:
+            self.__dict__[name] = value
+
+    def pairs(self):
+        name = self.name
+        value = self.value
+        if name is None or value is None or self.disabled:
+            return []
+        return [(name, value)]
+
+    def __str__(self):
+        name = self.name
+        value = self.value
+        if name is None: name = "<None>"
+        if value is None: value = "<None>"
+
+        infos = []
+        if self.disabled: infos.append("disabled")
+        if self.readonly: infos.append("readonly")
+        info = string.join(infos, ", ")
+        if info: info = " (%s)" % info
+
+        return "<%s(%s=%s)%s>" % (self.__class__.__name__, name, value, info)
+
+
+#---------------------------------------------------
+class TextControl(ScalarControl):
+    """Textual input control.
+
+    Covers:
+
+    INPUT/TEXT
+    INPUT/PASSWORD
+    INPUT/FILE
+    INPUT/HIDDEN
+    TEXTAREA
+
+    """
+    def __init__(self, type, name, attrs):
+        ScalarControl.__init__(self, type, name, attrs)
+        if self.type == "hidden": self.readonly = True
+        if self._value is None:
+            self._value = ""
+
+
+#---------------------------------------------------
+class FileControl(ScalarControl):
+    """File upload with INPUT TYPE=FILE.
+
+    The value attribute of a FileControl is always None.
+
+    Additional public method: add_file
+
+    """
+    def __init__(self, type, name, attrs):
+        ScalarControl.__init__(self, type, name, attrs)
+        self._value = None
+        self._upload_data = []
+
+    def __setattr__(self, name, value):
+        if name in ("value", "name", "type"):
+            raise AttributeError("%s attribute is readonly" % name)
+        else:
+            self.__dict__[name] = value
+
+    def add_file(self, file_object, content_type=None, filename=None):
+        if not hasattr(file_object, "read"):
+            raise TypeError("file-like object must have read method")
+        if content_type is not None and not isstringlike(content_type):
+            raise TypeError("content type must be None or string-like")
+        if filename is not None and not isstringlike(filename):
+            raise TypeError("filename must be None or string-like")
+        if content_type is None:
+            content_type = "application/octet-stream"
+        self._upload_data.append((file_object, content_type, filename))
+
+    def pairs(self):
+        # XXX should it be successful even if unnamed?
+        if self.name is None or self.disabled:
+            return []
+        return [(self.name, "")]
+
+    def _write_mime_data(self, mw):
+        # called by HTMLForm
+        if len(self._upload_data) == 1:
+            # single file
+            file_object, content_type, filename = self._upload_data[0]
+            mw2 = mw.nextpart()
+            fn_part = filename and ('; filename="%s"' % filename) or ''
+            disp = 'form-data; name="%s"%s' % (self.name, fn_part)
+            mw2.addheader("Content-disposition", disp, prefix=1)
+            fh = mw2.startbody(content_type, prefix=0)
+            fh.write(file_object.read())
+        elif len(self._upload_data) != 0:
+            # multiple files
+            mw2 = mw.nextpart()
+            disp = 'form-data; name="%s"' % self.name
+            mw2.addheader("Content-disposition", disp, prefix=1)
+            fh = mw2.startmultipartbody("mixed", prefix=0)
+            for file_object, content_type, filename in self._upload_data:
+                mw3 = mw2.nextpart()
+                fn_part = filename and ('; filename="%s"' % filename) or ''
+                disp = 'file%s' % fn_part
+                mw3.addheader("Content-disposition", disp, prefix=1)
+                fh2 = mw3.startbody(content_type, prefix=0)
+                fh2.write(file_object.read())
+            mw2.lastpart()
+
+    def __str__(self):
+        name = self.name
+        if name is None: name = "<None>"
+
+        if not self._upload_data:
+            value = "<No files added>"
+        else:
+            value = []
+            for file, ctype, filename in self._upload_data:
+                if filename is None:
+                    value.append("<Unnamed file>")
+                else:
+                    value.append(filename)
+            value = string.join(value, ", ")
+
+        info = []
+        if self.disabled: info.append("disabled")
+        if self.readonly: info.append("readonly")
+        info = string.join(info, ", ")
+        if info: info = " (%s)" % info
+
+        return "<%s(%s=%s)%s>" % (self.__class__.__name__, name, value, info)
+
+
+#---------------------------------------------------
+class IsindexControl(ScalarControl):
+    """ISINDEX control.
+
+    ISINDEX is the odd-one-out of HTML form controls.  In fact, it isn't really
+    part of regular HTML forms at all, and predates it.  You're only allowed
+    one ISINDEX per HTML document.  ISINDEX and regular form submission are
+    mutually exclusive -- either submit a form, or the ISINDEX.
+
+    Having said this, since ISINDEX controls may appear in forms (which is
+    probably bad HTML), ParseFile / ParseResponse will include them in the
+    HTMLForm instances it returns.  You can set the ISINDEX's value, as with
+    any other control (but note that ISINDEX controls have no name, so you'll
+    need to use the type argument of set_value!).  When you submit the form,
+    the ISINDEX will not be successful (ie., no data will get returned to the
+    server as a result of its presence), unless you click on the ISINDEX
+    control, in which case the ISINDEX gets submitted instead of the form:
+
+    form.set_value("my isindex value", type="isindex")
+    urllib2.urlopen(form.click(type="isindex"))
+
+    ISINDEX elements outside of FORMs are ignored.  If you want to submit one
+    by hand, do it like so:
+
+    url = urlparse.urljoin(page_uri, "?"+urllib.quote_plus("my isindex value"))
+    result = urllib2.urlopen(url)
+
+    """
+    def __init__(self, type, name, attrs):
+        ScalarControl.__init__(self, type, name, attrs)
+        if self._value is None:
+            self._value = ""
+
+    def pairs(self):
+        return []
+
+    def _click(self, form, coord, return_type):
+        # Relative URL for ISINDEX submission: instead of "foo=bar+baz",
+        # want "bar+baz".
+        # This doesn't seem to be specified in HTML 4.01 spec. (ISINDEX is
+        # deprecated in 4.01, but it should still say how to submit it).
+        # Submission of ISINDEX is explained in the HTML 3.2 spec, though.
+        url = urljoin(form.action, "?"+urllib.quote_plus(self.value))
+        req_data = url, None, []
+
+        if return_type == "pairs":
+            return []
+        elif return_type == "request_data":
+            return req_data
+        else:
+            return urllib2.Request(url)
+
+    def __str__(self):
+        value = self.value
+        if value is None: value = "<None>"
+
+        infos = []
+        if self.disabled: infos.append("disabled")
+        if self.readonly: infos.append("readonly")
+        info = string.join(infos, ", ")
+        if info: info = " (%s)" % info
+
+        return "<%s(%s)%s>" % (self.__class__.__name__, value, info)
+
+
+#---------------------------------------------------
+class IgnoreControl(ScalarControl):
+    """Control that we're not interested in.
+
+    Covers:
+
+    INPUT/RESET
+    BUTTON/RESET
+    INPUT/BUTTON
+    BUTTON/BUTTON
+
+    These controls are always unsuccessful, in the terminology of HTML 4 (ie.
+    they never require any information to be returned to the server).
+
+    BUTTON/BUTTON is used to generate events for script embedded in HTML.
+
+    The value attribute of IgnoreControl is always None.
+
+    """
+    def __init__(self, type, name, attrs):
+        ScalarControl.__init__(self, type, name, attrs)
+        self._value = None
+
+    def __setattr__(self, name, value):
+        if name == "value":
+            raise AttributeError(
+                "control '%s' is ignored, hence read-only" % self.name)
+        elif name in ("name", "type"):
+            raise AttributeError("%s attribute is readonly" % name)
+        else:
+            self.__dict__[name] = value
+
+
+#---------------------------------------------------
+class ListControl(Control):
+    """Control representing a sequence of items.
+
+    The value attribute of a ListControl represents the selected list items in
+    the control.
+
+    ListControl implements both list controls that take a single value and
+    those that take multiple values.
+
+    ListControls accept sequence values only.  Some controls only accept
+    sequences of length 0 or 1 (RADIO, and single-selection SELECT).
+    In those cases, ItemCountError is raised if len(sequence) > 1.  CHECKBOXes
+    and multiple-selection SELECTs (those having the "multiple" HTML attribute)
+    accept sequences of any length.
+
+    Note the following mistake:
+
+    control.value = some_value
+    assert control.value == some_value    # not necessarily true
+
+    The reason for this is that the value attribute always gives the list items
+    in the order they were listed in the HTML.
+
+    ListControl items can also be referred to by their labels instead of names.
+    Use the by_label argument, and the set_value_by_label, get_value_by_label
+    methods.
+
+    XXX RadioControl and CheckboxControl don't implement by_label yet.
+
+    Note that, rather confusingly, though SELECT controls are represented in
+    HTML by SELECT elements (which contain OPTION elements, representing
+    individual list items), CHECKBOXes and RADIOs are not represented by *any*
+    element.  Instead, those controls are represented by a collection of INPUT
+    elements.  For example, this is a SELECT control, named "control1":
+
+    <select name="control1">
+     <option>foo</option>
+     <option value="1">bar</option>
+    </select>
+
+    and this is a CHECKBOX control, named "control2":
+
+    <input type="checkbox" name="control2" value="foo" id="cbe1">
+    <input type="checkbox" name="control2" value="bar" id="cbe2">
+
+    The id attribute of a CHECKBOX or RADIO ListControl is always that of its
+    first element (for example, "cbe1" above).
+
+
+    Additional read-only public attribute: multiple.
+
+
+    ListControls are built up by the parser from their component items by
+    creating one ListControl per item, consolidating them into a single master
+    ListControl held by the HTMLForm:
+
+    -User calls form.new_control(...)
+    -Form creates Control, and calls control.add_to_form(self).
+    -Control looks for a Control with the same name and type in the form, and
+    if it finds one, merges itself with that control by calling
+    control.merge_control(self).  The first Control added to the form, of a
+    particular name and type, is the only one that survives in the form.
+    -Form calls control.fixup for all its controls.  ListControls in the form
+    know they can now safely pick their default values.
+
+    To create a ListControl without an HTMLForm, use:
+
+    control.merge_control(new_control)
+
+    """
+    def __init__(self, type, name, attrs={}, select_default=False,
+                 called_as_base_class=False):
+        """
+        select_default: for RADIO and multiple-selection SELECT controls, pick
+         the first item as the default if no 'selected' HTML attribute is
+         present
+
+        """
+        if not called_as_base_class:
+            raise NotImplementedError()
+
+        self.__dict__["type"] = string.lower(type)
+        self.__dict__["name"] = name
+        self._value = attrs.get("value")
+        self.disabled = False
+        self.readonly = False
+        self.id = attrs.get("id")
+
+        self._attrs = attrs.copy()
+        # As Controls are merged in with .merge_control(), self._attrs will
+        # refer to each Control in turn -- always the most recently merged
+        # control.  Each merged-in Control instance corresponds to a single
+        # list item: see ListControl.__doc__.
+        if attrs:
+            self._attrs_list = [self._attrs]  # extended by .merge_control()
+            self._disabled_list = [self._attrs.has_key("disabled")]  # ditto
+        else:
+            self._attrs_list = []  # extended by .merge_control()
+            self._disabled_list = []  # ditto
+
+        self._select_default = select_default
+        self._clicked = False
+        # Some list controls can have their default set only after all items
+        # are known.  If so, self._value_is_set is false, and the self.fixup
+        # method, called after all items have been added, sets the default.
+        self._value_is_set = False
+
+    def _value_from_label(self, label):
+        raise NotImplementedError("control '%s' does not yet support "
+                                  "by_label" % self.name)
+
+    def toggle(self, name, by_label=False):
+        return self._set_selected_state(name, 2, by_label)
+    def set(self, selected, name, by_label=False):
+        action = int(bool(selected))
+        return self._set_selected_state(name, action, by_label)
+
+    def _set_selected_state(self, name, action, by_label):
+        """
+        name: item name
+        action:
+         0: clear
+         1: set
+         2: toggle
+
+        """
+        if not isstringlike(name):
+            raise TypeError("item name must be string-like")
+        if self.disabled:
+            raise AttributeError("control '%s' is disabled" % self.name)
+        if self.readonly:
+            raise AttributeError("control '%s' is readonly" % self.name)
+        if by_label:
+            name = self._value_from_label(name)
+        try:
+            i = self._menu.index(name)
+        except ValueError:
+            raise ItemNotFoundError("no item named '%s'" % name)
+
+        if self.multiple:
+            if action == 2:
+                action = not self._selected[i]
+            if action and self._disabled_list[i]:
+                raise AttributeError("item '%s' is disabled" % name)
+            self._selected[i] = bool(action)
+        else:
+            if action == 2:
+                if self._selected == name:
+                    action = 0
+                else:
+                    action = 1
+            if action == 0 and self._selected == name:
+                self._selected = None
+            elif action == 1:
+                if self._disabled_list[i]:
+                    raise AttributeError("item '%s' is disabled" % name)
+                self._selected = name
+
+    def toggle_single(self, by_label=False):
+        self._set_single_selected_state(2, by_label)
+    def set_single(self, selected, by_label=False):
+        action = int(bool(selected))
+        self._set_single_selected_state(action, by_label)
+
+    def _set_single_selected_state(self, action, by_label):
+        if len(self._menu) != 1:
+            raise ItemCountError("'%s' is not a single-item control" %
+                                 self.name)
+
+        name = self._menu[0]
+        if by_label:
+            name = self._value_from_label(name)
+        self._set_selected_state(name, action, by_label)
+
+    def get_item_disabled(self, name, by_label=False):
+        """Get disabled state of named list item in a ListControl."""
+        if by_label:
+            name = self._value_from_label(name)
+        try:
+            i = self._menu.index(name)
+        except ValueError:
+            raise ItemNotFoundError()
+        else:
+            return self._disabled_list[i]
+
+    def set_item_disabled(self, disabled, name, by_label=False):
+        """Set disabled state of named list item in a ListControl.
+
+        disabled: boolean disabled state
+
+        """
+        if by_label:
+            name = self._value_from_label(name)
+        try:
+            i = self._menu.index(name)
+        except ValueError:
+            raise ItemNotFoundError()
+        else:
+            self._disabled_list[i] = bool(disabled)
+
+    def set_all_items_disabled(self, disabled):
+        """Set disabled state of all list items in a ListControl.
+
+        disabled: boolean disabled state
+
+        """
+        for i in range(len(self._disabled_list)):
+            self._disabled_list[i] = bool(disabled)
+
+    def get_item_attrs(self, name, by_label=False):
+        """Return dictionary of HTML attributes for a single ListControl item.
+
+        The HTML element types that describe list items are: OPTION for SELECT
+        controls, INPUT for the rest.  These elements have HTML attributes that
+        you may occasionally want to know about -- for example, the "alt" HTML
+        attribute gives a text string describing the item (graphical browsers
+        usually display this as a tooltip).
+
+        The returned dictionary maps HTML attribute names to values.  The names
+        and values are taken from the original HTML.
+
+        Note that for SELECT controls, the returned dictionary contains a
+        special key "contents" -- see SelectControl.__doc__.
+
+        """
+        if by_label:
+            name = self._value_from_label(name)
+        try:
+            i = self._menu.index(name)
+        except ValueError:
+            raise ItemNotFoundError()
+        return self._attrs_list[i]
+
+    def add_to_form(self, form):
+        try:
+            control = form.find_control(self.name, self.type)
+        except ControlNotFoundError:
+            Control.add_to_form(self, form)
+        else:
+            control.merge_control(self)
+
+    def merge_control(self, control):
+        assert bool(control.multiple) == bool(self.multiple)
+        assert isinstance(control, self.__class__)
+        self._menu.extend(control._menu)
+        self._attrs_list.extend(control._attrs_list)
+        self._disabled_list.extend(control._disabled_list)
+        if control.multiple:
+            self._selected.extend(control._selected)
+        else:
+            if control._value_is_set:
+                self._selected = control._selected
+        if control._value_is_set:
+            self._value_is_set = True
+
+    def fixup(self):
+        """
+        ListControls are built up from component list items (which are also
+        ListControls) during parsing.  This method should be called after all
+        items have been added.  See ListControl.__doc__ for the reason this is
+        required.
+
+        """
+        # Need to set default selection where no item was indicated as being
+        # selected by the HTML:
+
+        # CHECKBOX:
+        #  Nothing should be selected.
+        # SELECT/single, SELECT/multiple and RADIO:
+        #  RFC 1866 (HTML 2.0): says first item should be selected.
+        #  W3C HTML 4.01 Specification: says that client behaviour is
+        #   undefined in this case.  For RADIO, exactly one must be selected,
+        #   though which one is undefined.
+        #  Both Netscape and Microsoft Internet Explorer (IE) choose first
+        #   item for SELECT/single.  However, both IE5 and Mozilla (both 1.0
+        #   and Firebird 0.6) leave all items unselected for RADIO and
+        #   SELECT/multiple.
+
+        # Since both Netscape and IE all choose the first item for
+        # SELECT/single, we do the same.  OTOH, both Netscape and IE
+        # leave SELECT/multiple with nothing selected, in violation of RFC 1866
+        # (but not in violation of the W3C HTML 4 standard); the same is true
+        # of RADIO (which *is* in violation of the HTML 4 standard).  We follow
+        # RFC 1866 if the select_default attribute is set, and Netscape and IE
+        # otherwise.  RFC 1866 and HTML 4 are always violated insofar as you
+        # can deselect all items in a RadioControl.
+
+        raise NotImplementedError()
+
+    def __getattr__(self, name):
+        if name == "value":
+            menu = self._menu
+            if self.multiple:
+                values = []
+                for i in range(len(menu)):
+                    if self._selected[i]: values.append(menu[i])
+                return values
+            else:
+                if self._selected is None: return []
+                else: return [self._selected]
+        else:
+            raise AttributeError("%s instance has no attribute '%s'" %
+                                 (self.__class__.__name__, name))
+
+    def __setattr__(self, name, value):
+        if name == "value":
+            if self.disabled:
+                raise AttributeError("control '%s' is disabled" % self.name)
+            if self.readonly:
+                raise AttributeError("control '%s' is readonly" % self.name)
+            self._set_value(value)
+        elif name in ("name", "type", "multiple"):
+            raise AttributeError("%s attribute is readonly" % name)
+        else:
+            self.__dict__[name] = value
+
+    def _set_value(self, value):
+        if self.multiple:
+            self._multiple_set_value(value)
+        else:
+            self._single_set_value(value)
+
+    def _single_set_value(self, value):
+        if value is None or isstringlike(value):
+            raise TypeError("ListControl, must set a sequence")
+        nr = len(value)
+        if not (0 <= nr <= 1):
+            raise ItemCountError("single selection list, must set sequence of "
+                                 "length 0 or 1")
+
+        if nr == 0:
+            self._selected = None
+        else:
+            value = value[0]
+            try:
+                i = self._menu.index(value)
+            except ValueError:
+                raise ItemNotFoundError("no item named '%s'" %
+                                        repr(value))
+            if self._disabled_list[i]:
+                raise AttributeError("item '%s' is disabled" % value)
+            self._selected = value
+
+    def _multiple_set_value(self, value):
+        if value is None or isstringlike(value):
+            raise TypeError("ListControl, must set a sequence")
+
+        selected = [False]*len(self._selected)
+        menu = self._menu
+        disabled_list = self._disabled_list
+
+        for v in value:
+            found = False
+            for i in range(len(menu)):
+                item_name = menu[i]
+                if v == item_name:
+                    if disabled_list[i]:
+                        raise AttributeError("item '%s' is disabled" % value)
+                    selected[i] = True
+                    found = True
+                    break
+            if not found:
+                raise ItemNotFoundError("no item named '%s'" % repr(v))
+        self._selected = selected
+
+    def set_value_by_label(self, value):
+        raise NotImplementedError("control '%s' does not yet support "
+                                  "by_label" % self.name)
+    def get_value_by_label(self):
+        raise NotImplementedError("control '%s' does not yet support "
+                                  "by_label" % self.name)
+
+    def possible_items(self, by_label=False):
+        if by_label:
+            raise NotImplementedError(
+                "control '%s' does not yet support by_label" % self.name)
+        return copy.copy(self._menu)
+
+    def pairs(self):
+        if self.disabled:
+            return []
+
+        if not self.multiple:
+            name = self.name
+            value = self._selected
+            if name is None or value is None:
+                return []
+            return [(name, value)]
+        else:
+            control_name = self.name  # usually the name HTML attribute
+            pairs = []
+            for i in range(len(self._menu)):
+                item_name = self._menu[i]  # usually the value HTML attribute
+                if self._selected[i]:
+                    pairs.append((control_name, item_name))
+            return pairs
+
+    def _item_str(self, i):
+        item_name = self._menu[i]
+        if self.multiple:
+            if self._selected[i]:
+                item_name = "*"+item_name
+        else:
+            if self._selected == item_name:
+                item_name = "*"+item_name
+        if self._disabled_list[i]:
+            item_name = "(%s)" % item_name
+        return item_name
+
+    def __str__(self):
+        name = self.name
+        if name is None: name = "<None>"
+
+        display = []
+        for i in range(len(self._menu)):
+            s = self._item_str(i)
+            display.append(s)
+
+        infos = []
+        if self.disabled: infos.append("disabled")
+        if self.readonly: infos.append("readonly")
+        info = string.join(infos, ", ")
+        if info: info = " (%s)" % info
+
+        return "<%s(%s=[%s])%s>" % (self.__class__.__name__,
+                                    name, string.join(display, ", "), info)
+
+
+class RadioControl(ListControl):
+    """
+    Covers:
+
+    INPUT/RADIO
+
+    """
+    def __init__(self, type, name, attrs, select_default=False):
+        ListControl.__init__(self, type, name, attrs, select_default,
+                             called_as_base_class=True)
+        self.__dict__["multiple"] = False
+        value = attrs.get("value", "on")
+        self._menu = [value]
+        checked = attrs.has_key("checked")
+        if checked:
+            self._value_is_set = True
+            self._selected = value
+        else:
+            self._selected = None
+
+    def fixup(self):
+        if not self._value_is_set:
+            # no item explicitly selected
+            assert self._selected is None
+            if self._select_default:
+                self._selected = self._menu[0]
+            self._value_is_set = True
+
+
+class CheckboxControl(ListControl):
+    """
+    Covers:
+
+    INPUT/CHECKBOX
+
+    """
+    def __init__(self, type, name, attrs, select_default=False):
+        ListControl.__init__(self, type, name, attrs, select_default,
+                             called_as_base_class=True)
+        self.__dict__["multiple"] = True
+        value = attrs.get("value", "on")
+        self._menu = [value]
+        checked = attrs.has_key("checked")
+        self._selected = [checked]
+        self._value_is_set = True
+
+    def fixup(self):
+        # If no items were explicitly checked in HTML, that's how we must
+        # leave it, so we have nothing to do here.
+        assert self._value_is_set
+
+
+class SelectControl(ListControl):
+    """
+    Covers:
+
+    SELECT (and OPTION)
+
+    SELECT control values and labels are subject to some messy defaulting
+    rules.  For example, if the HTML repreentation of the control is:
+
+    <SELECT name=year>
+      <OPTION value=0 label="2002">current year</OPTION>
+      <OPTION value=1>2001</OPTION>
+      <OPTION>2000</OPTION>
+    </SELECT>
+
+    The items, in order, have labels "2002", "2001" and "2000", whereas their
+    values are "0", "1" and "2000" respectively.  Note that the value of the
+    last OPTION in this example defaults to its contents, as specified by RFC
+    1866, as do the labels of the second and third OPTIONs.
+
+    The purpose of these methods is that the OPTION labels are sometimes much
+    more meaningful, than are the OPTION values, which can make for more
+    maintainable code.
+
+    Additional read-only public attribute: attrs
+
+    The attrs attribute is a dictionary of the original HTML attributes of the
+    SELECT element.  Other ListControls do not have this attribute, because in
+    other cases the control as a whole does not correspond to any single HTML
+    element.  The get_item_attrs method may be used as usual to get at the
+    HTML attributes of the HTML elements corresponding to individual list items
+    (for SELECT controls, these are OPTION elements).
+
+    Another special case is that the attributes dictionaries returned by
+    get_item_attrs have a special key "contents" which does not correspond to
+    any real HTML attribute, but rather contains the contents of the OPTION
+    element:
+
+    <OPTION>this bit</OPTION>
+
+    """
+    # HTML attributes here are treated slightly from other list controls:
+    # -The SELECT HTML attributes dictionary is stuffed into the OPTION
+    #  HTML attributes dictionary under the "__select" key.
+    # -The content of each OPTION element is stored under the special
+    #  "contents" key of the dictionary.
+    # After all this, the dictionary is passed to the SelectControl constructor
+    # as the attrs argument, as usual.  However:
+    # -The first SelectControl constructed when building up a SELECT control
+    #  has a constructor attrs argument containing only the __select key -- so
+    #  this SelectControl represents an empty SELECT control.
+    # -Subsequent SelectControls have both OPTION HTML-attribute in attrs and
+    #  the __select dictionary containing the SELECT HTML-attributes.
+    def __init__(self, type, name, attrs, select_default=False):
+        # fish out the SELECT HTML attributes from the OPTION HTML attributes
+        # dictionary
+        self.attrs = attrs["__select"].copy()
+        attrs = attrs.copy()
+        del attrs["__select"]
+
+        ListControl.__init__(self, type, name, attrs, select_default,
+                             called_as_base_class=True)
+
+        self._label_map = None
+        self.disabled = self.attrs.has_key("disabled")
+        self.id = self.attrs.get("id")
+
+        self._menu = []
+        self._selected = []
+        self._value_is_set = False
+        if self.attrs.has_key("multiple"):
+            self.__dict__["multiple"] = True
+            self._selected = []
+        else:
+            self.__dict__["multiple"] = False
+            self._selected = None
+
+        if attrs:  # OPTION item data was provided
+            value = attrs["value"]
+            self._menu.append(value)
+            selected = attrs.has_key("selected")
+            if selected:
+                self._value_is_set = True
+            if self.attrs.has_key("multiple"):
+                self._selected.append(selected)
+            elif selected:
+                self._selected = value
+
+    def _build_select_label_map(self):
+        """Return an ordered mapping of labels to values.
+
+        For example, if the HTML repreentation of the control is as given in
+        SelectControl.__doc__,  this function will return a mapping like:
+
+        {"2002": "0", "2001": "1", "2000": "2000"}
+
+        """
+        alist = []
+        for val in self._menu:
+            attrs = self.get_item_attrs(val)
+            alist.append((attrs["label"], val))
+        return AList(alist)
+
+    def _value_from_label(self, label):
+        try:
+            return self._label_map[label]
+        except KeyError:
+            raise ItemNotFoundError("no item has label '%s'" % label)
+
+    def fixup(self):
+        if not self._value_is_set:
+            # No item explicitly selected.
+            if len(self._menu) > 0:
+                if self.multiple:
+                    if self._select_default:
+                        self._selected[0] = True
+                else:
+                    assert self._selected is None
+                    self._selected = self._menu[0]
+            self._value_is_set = True
+        self._label_map = self._build_select_label_map()
+
+    def possible_items(self, by_label=False):
+        if not by_label:
+            return copy.copy(self._menu)
+        else:
+            self._label_map.set_inverted(True)
+            try:
+                r = map(lambda v, self=self: self._label_map[v], self._menu)
+            finally:
+                self._label_map.set_inverted(False)
+            return r
+
+    def set_value_by_label(self, value):
+        if isstringlike(value):
+            raise TypeError("ListControl, must set a sequence, not a string")
+        if self.disabled:
+            raise AttributeError("control '%s' is disabled" % self.name)
+        if self.readonly:
+            raise AttributeError("control '%s' is readonly" % self.name)
+
+        try:
+            value = map(lambda v, self=self: self._label_map[v], value)
+        except KeyError, e:
+            raise ItemNotFoundError("no item has label '%s'" % e.args[0])
+        self._set_value(value)
+
+    def get_value_by_label(self):
+        menu = self._menu
+        self._label_map.set_inverted(True)
+        try:
+            if self.multiple:
+                values = []
+                for i in range(len(menu)):
+                    if self._selected[i]:
+                        values.append(self._label_map[menu[i]])
+                return values
+            else:
+                return [self._label_map[self._selected]]
+        finally:
+            self._label_map.set_inverted(False)
+
+
+#---------------------------------------------------
+class SubmitControl(ScalarControl):
+    """
+    Covers:
+
+    INPUT/SUBMIT
+    BUTTON/SUBMIT
+
+    """
+    def __init__(self, type, name, attrs):
+        ScalarControl.__init__(self, type, name, attrs)
+        # IE5 defaults SUBMIT value to "Submit Query"; Firebird 0.6 leaves it
+        # blank, Konqueror 3.1 defaults to "Submit".  HTML spec. doesn't seem
+        # to define this.
+        if self.value is None: self.value = ""
+        self.readonly = True
+
+    def _click(self, form, coord, return_type):
+        self._clicked = coord
+        r = form._switch_click(return_type)
+        self._clicked = False
+        return r
+
+    def pairs(self):
+        if not self._clicked:
+            return []
+        return ScalarControl.pairs(self)
+
+
+#---------------------------------------------------
+class ImageControl(SubmitControl):
+    """
+    Covers:
+
+    INPUT/IMAGE
+
+    The value attribute of an ImageControl is always None.  Coordinates are
+    specified using one of the HTMLForm.click* methods.
+
+    """
+    def __init__(self, type, name, attrs):
+        ScalarControl.__init__(self, type, name, attrs)
+        self.__dict__["value"] = None
+
+    def __setattr__(self, name, value):
+        if name in ("value", "name", "type"):
+            raise AttributeError("%s attribute is readonly" % name)
+        else:
+            self.__dict__[name] = value
+
+    def pairs(self):
+        clicked = self._clicked
+        if self.disabled or not clicked:
+            return []
+        name = self.name
+        if name is None: return []
+        return [("%s.x" % name, str(clicked[0])),
+                ("%s.y" % name, str(clicked[1]))]
+
+
+# aliases, just to make str(control) and str(form) clearer
+class PasswordControl(TextControl): pass
+class HiddenControl(TextControl): pass
+class TextareaControl(TextControl): pass
+class SubmitButtonControl(SubmitControl): pass
+
+
+def is_listcontrol(control): return isinstance(control, ListControl)
+
+
+class HTMLForm:
+    """Represents a single HTML <form> ... </form> element.
+
+    A form consists of a sequence of controls that usually have names, and
+    which can take on various values.  The values of the various types of
+    controls represent variously: text, zero-, one- or many-of-many choices,
+    and files to be uploaded.
+
+    Forms can be filled in with data to be returned to the server, and then
+    submitted, using the click method to generate a request object suitable for
+    passing to urllib2.urlopen (or the click_request_data or click_pairs
+    methods if you're not using urllib2).
+
+    import ClientForm
+    forms = ClientForm.ParseFile(html, base_uri)
+    form = forms[0]
+
+    form["query"] = "Python"
+    form.set("lots", "nr_results")
+
+    response = urllib2.urlopen(form.click())
+
+    Usually, HTMLForm instances are not created directly.  Instead, the
+    ParseFile or ParseResponse factory functions are used.  If you do construct
+    HTMLForm objects yourself, however, note that an HTMLForm instance is only
+    properly initialised after the fixup method has been called (ParseFile and
+    ParseResponse do this for you).  See ListControl.__doc__ for the reason
+    this is required.
+
+    Indexing a form (form["control_name"]) returns the named Control's value
+    attribute.  Assignment to a form index (form["control_name"] = something)
+    is equivalent to assignment to the named Control's value attribute.  If you
+    need to be more specific than just supplying the control's name, use the
+    set_value and get_value methods.
+
+    ListControl values are lists of item names.  The list item's name is the
+    value of the corresponding HTML element's "value" attribute.
+
+    Example:
+
+      <INPUT type="CHECKBOX" name="cheeses" value="leicester"></INPUT>
+      <INPUT type="CHECKBOX" name="cheeses" value="cheddar"></INPUT>
+
+    defines a CHECKBOX control with name "cheeses" which has two items, named
+    "leicester" and "cheddar".
+
+    Another example:
+
+      <SELECT name="more_cheeses">
+        <OPTION>1</OPTION>
+        <OPTION value="2" label="CHEDDAR">cheddar</OPTION>
+      </SELECT>
+
+    defines a SELECT control with name "more_cheeses" which has two items,
+    named "1" and "2".
+
+    To set, clear or toggle individual list items, use the set and toggle
+    methods.  To set the whole value, do as for any other control:use indexing
+    or the set_/get_value methods.
+
+    Example:
+
+    # select *only* the item named "cheddar"
+    form["cheeses"] = ["cheddar"]
+    # select "cheddar", leave other items unaffected
+    form.set("cheddar", "cheeses")
+
+    Some controls (RADIO and SELECT without the multiple attribute) can only
+    have zero or one items selected at a time.  Some controls (CHECKBOX and
+    SELECT with the multiple attribute) can have multiple items selected at a
+    time.  To set the whole value of a multiple-selection ListControl, assign a
+    sequence to a form index:
+
+    form["cheeses"] = ["cheddar", "leicester"]
+
+    To check whether a control has an item, or whether an item is selected,
+    respectively:
+
+    "cheddar" in form.possible_items("cheeses")
+    "cheddar" in form["cheeses"]  # (or "cheddar" in form.get_value("cheeses"))
+
+    Note that some items may be disabled (see below).
+
+    Note the following mistake:
+
+    form[control_name] = control_value
+    assert form[control_name] == control_value  # not necessarily true
+
+    The reason for this is that form[control_name] always gives the list items
+    in the order they were listed in the HTML.
+
+    List items (hence list values, too) can be referred to in terms of list
+    item labels rather than list item names.  Currently, this is only possible
+    for SELECT controls (this is a bug).  To use this feature, use the by_label
+    arguments to the various HTMLForm methods.  Note that it is *item* names
+    (hence ListControl values also), not *control* names, that can be referred
+    to by label.
+
+    The question of default values of OPTION contents, labels and values is
+    somewhat complicated: see SelectControl.__doc__ and
+    ListControl.get_item_attrs.__doc__ if you think you need to know.
+
+    Controls can be disabled or readonly.  In either case, the control's value
+    cannot be changed until you clear those flags (using the methods on
+    HTMLForm).  Disabled is the state typically represented by browsers by
+    `greying out' a control.  Disabled controls are not `successful' -- they
+    don't cause data to get returned to the server.  Readonly controls usually
+    appear in browsers as read-only text boxes.  Readonly controls are
+    successful.  List items can also be disabled.  Attempts to select disabled
+    items (with form[name] = value, or using the ListControl.set method, for
+    example) fail.  Attempts to clear disabled items are allowed.
+
+    If a lot of controls are readonly, it can be useful to do this:
+
+    form.set_all_readonly(False)
+
+    When you want to do several things with a single control, or want to do
+    less common things, like changing which controls and items are disabled,
+    you can get at a particular control:
+
+    control = form.find_control("cheeses")
+    control.set_item_disabled(False, "gruyere")
+    control.set("gruyere")
+
+    Most methods on HTMLForm just delegate to the contained controls, so see
+    the docstrings of the various Control classes for further documentation.
+    Most of these delegating methods take name, type, kind, id and nr arguments
+    to specify the control to be operated on: see
+    HTMLForm.find_control.__doc__.
+
+    ControlNotFoundError (subclass of ValueError) is raised if the specified
+    control can't be found.  This includes occasions where a non-ListControl
+    is found, but the method (set, for example) requires a ListControl.
+    ItemNotFoundError (subclass of ValueError) is raised if a list item can't
+    be found.  ItemCountError (subclass of ValueError) is raised if an attempt
+    is made to select more than one item and the control doesn't allow that, or
+    set/get_single are called and the control contains more than one item.
+    AttributeError is raised if a control or item is readonly or disabled and
+    an attempt is made to alter its value.
+
+    XXX CheckBoxControl and RadioControl don't yet support item access by label
+
+    Security note: Remember that any passwords you store in HTMLForm instances
+    will be saved to disk in the clear if you pickle them (directly or
+    indirectly).  The simplest solution to this is to avoid pickling HTMLForm
+    objects.  You could also pickle before filling in any password, or just set
+    the password to "" before pickling.
+
+
+    Public attributes:
+
+    action: full (absolute URI) form action
+    method: "GET" or "POST"
+    enctype: form transfer encoding MIME type
+    name: name of form (None if no name was specified)
+    attrs: dictionary mapping original HTML form attributes to their values
+
+    controls: list of Control instances; do not alter this list
+     (instead, call form.new_control to make a Control and add it to the
+     form, or control.add_to_form if you already have a Control instance)
+
+
+
+    Methods for form filling:
+    -------------------------
+
+    Most of the these methods have very similar arguments.  See
+    HTMLForm.find_control.__doc__ for details of the name, type, kind and nr
+    arguments.  See above for a description of by_label.
+
+    def find_control(self,
+                     name=None, type=None, kind=None, id=None, predicate=None,
+                     nr=None)
+
+    get_value(name=None, type=None, kind=None, id=None, nr=None,
+              by_label=False)
+    set_value(value,
+              name=None, type=None, kind=None, id=None, nr=None,
+              by_label=False)
+
+    set_all_readonly(readonly)
+
+
+    Methods applying only to ListControls:
+
+    possible_items(name=None, type=None, kind=None, id=None, nr=None,
+                   by_label=False)
+
+    set(selected, item_name,
+        name=None, type=None, kind=None, id=None, nr=None,
+        by_label=False)
+    toggle(item_name,
+           name=None, type=None, id=None, nr=None,
+           by_label=False)
+
+    set_single(selected,
+               name=None, type=None, kind=None, id=None, nr=None,
+               by_label=False)
+    toggle_single(name=None, type=None, kind=None, id=None, nr=None,
+                  by_label=False)
+
+
+    Method applying only to FileControls:
+
+    add_file(file_object,
+             content_type="application/octet-stream", filename=None,
+             name=None, id=None, nr=None)
+
+
+    Methods applying only to clickable controls:
+
+    click(name=None, type=None, id=None, nr=0, coord=(1,1))
+    click_request_data(name=None, type=None, id=None, nr=0, coord=(1,1))
+    click_pairs(name=None, type=None, id=None, nr=0, coord=(1,1))
+
+    """
+
+    type2class = {
+        "text": TextControl,
+        "password": PasswordControl,
+        "hidden": HiddenControl,
+        "textarea": TextareaControl,
+
+        "isindex": IsindexControl,
+
+        "file": FileControl,
+
+        "button": IgnoreControl,
+        "buttonbutton": IgnoreControl,
+        "reset": IgnoreControl,
+        "resetbutton": IgnoreControl,
+
+        "submit": SubmitControl,
+        "submitbutton": SubmitButtonControl,
+        "image": ImageControl,
+
+        "radio": RadioControl,
+        "checkbox": CheckboxControl,
+        "select": SelectControl,
+        }
+
+#---------------------------------------------------
+# Initialisation.  Use ParseResponse / ParseFile instead.
+
+    def __init__(self, action, method="GET",
+                 enctype="application/x-www-form-urlencoded",
+                 name=None, attrs=None):
+        """
+        In the usual case, use ParseResponse (or ParseFile) to create new
+        HTMLForm objects.
+
+        action: full (absolute URI) form action
+        method: "GET" or "POST"
+        enctype: form transfer encoding MIME type
+        name: name of form
+        attrs: dictionary mapping original HTML form attributes to their values
+
+        """
+        self.action = action
+        self.method = method
+        self.enctype = enctype
+        self.name = name
+        if attrs is not None:
+            self.attrs = attrs.copy()
+        else:
+            self.attrs = {}
+        self.controls = []
+
+    def new_control(self, type, name, attrs,
+                    ignore_unknown=False, select_default=False):
+        """Adds a new control to the form.
+
+        This is usually called by ParseFile and ParseResponse.  Don't call it
+        youself unless you're building your own Control instances.
+
+        Note that controls representing lists of items are built up from
+        controls holding only a single list item.  See ListControl.__doc__ for
+        further information.
+
+        type: type of control (see Control.__doc__ for a list)
+        attrs: HTML attributes of control
+        ignore_unknown: if true, use a dummy Control instance for controls of
+         unknown type; otherwise, raise ValueError
+        select_default: for RADIO and multiple-selection SELECT controls, pick
+         the first item as the default if no 'selected' HTML attribute is
+         present (this defaulting happens when the HTMLForm.fixup method is
+         called)
+
+        """
+        type = string.lower(type)
+        klass = self.type2class.get(type)
+        if klass is None:
+            if ignore_unknown:
+                klass = IgnoreControl
+            else:
+                raise ValueError("Unknown control type '%s'" % type)
+
+        a = attrs.copy()
+        if issubclass(klass, ListControl):
+            control = klass(type, name, a, select_default)
+        else:
+            control = klass(type, name, a)
+        control.add_to_form(self)
+
+    def fixup(self):
+        """Normalise form after all controls have been added.
+
+        This is usually called by ParseFile and ParseResponse.  Don't call it
+        youself unless you're building your own Control instances.
+
+        This method should only be called once, after all controls have been
+        added to the form.
+
+        """
+        for control in self.controls:
+            control.fixup()
+
+#---------------------------------------------------
+    def __str__(self):
+        header = "%s %s %s" % (self.method, self.action, self.enctype)
+        rep = [header]
+        for control in self.controls:
+            rep.append("  %s" % str(control))
+        return "<%s>" % string.join(rep, "\n")
+
+#---------------------------------------------------
+# Form-filling methods.
+
+    def __getitem__(self, name):
+        return self.find_control(name).value
+    def __setitem__(self, name, value):
+        control = self.find_control(name)
+        try:
+            control.value = value
+        except AttributeError, e:
+            raise ValueError(str(e))
+
+    def get_value(self,
+                  name=None, type=None, kind=None, id=None, nr=None,
+                  by_label=False):
+        """Return value of control.
+
+        If only name and value arguments are supplied, equivalent to
+
+        form[name]
+
+        """
+        c = self.find_control(name, type, kind, id, nr=nr)
+        if by_label:
+            try:
+                meth = c.get_value_by_label
+            except AttributeError:
+                raise NotImplementedError(
+                    "control '%s' does not yet support by_label" % c.name)
+            else:
+                return meth()
+        else:
+            return c.value
+    def set_value(self, value,
+                  name=None, type=None, kind=None, id=None, nr=None,
+                  by_label=False):
+        """Set value of control.
+
+        If only name and value arguments are supplied, equivalent to
+
+        form[name] = value
+
+        """
+        c = self.find_control(name, type, kind, id, nr=nr)
+        if by_label:
+            try:
+                meth = c.set_value_by_label
+            except AttributeError:
+                raise NotImplementedError(
+                    "control '%s' does not yet support by_label" % c.name)
+            else:
+                meth(value)
+        else:
+            c.value = value
+
+    def set_all_readonly(self, readonly):
+        for control in self.controls:
+            control.readonly = bool(readonly)
+
+
+#---------------------------------------------------
+# Form-filling methods applying only to ListControls.
+
+    def possible_items(self,
+                       name=None, type=None, kind=None, id=None, nr=None,
+                       by_label=False):
+        """Return a list of all values that the specified control can take."""
+        c = self._find_list_control(name, type, kind, id, nr)
+        return c.possible_items(by_label)
+
+    def set(self, selected, item_name,
+            name=None, type=None, kind=None, id=None, nr=None,
+            by_label=False):
+        """Select / deselect named list item.
+
+        selected: boolean selected state
+
+        """
+        self._find_list_control(name, type, kind, id, nr).set(
+            selected, item_name, by_label)
+    def toggle(self, item_name,
+               name=None, type=None, kind=None, id=None, nr=None,
+               by_label=False):
+        """Toggle selected state of named list item."""
+        self._find_list_control(name, type, kind, id, nr).toggle(
+            item_name, by_label)
+
+    def set_single(self, selected,
+                   name=None, type=None, kind=None, id=None, nr=None,
+                   by_label=False):
+        """Select / deselect list item in a control having only one item.
+
+        If the control has multiple list items, ItemCountError is raised.
+
+        This is just a convenience method, so you don't need to know the item's
+        name -- the item name in these single-item controls is usually
+        something meaningless like "1" or "on".
+
+        For example, if a checkbox has a single item named "on", the following
+        two calls are equivalent:
+
+        control.toggle("on")
+        control.toggle_single()
+
+        """
+        self._find_list_control(name, type, kind, id, nr).set_single(
+            selected, by_label)
+    def toggle_single(self, name=None, type=None, kind=None, id=None, nr=None,
+                      by_label=False):
+        """Toggle selected state of list item in control having only one item.
+
+        The rest is as for HTMLForm.set_single.__doc__.
+
+        """
+        self._find_list_control(name, type, kind, id, nr).toggle_single(
+            by_label)
+
+#---------------------------------------------------
+# Form-filling method applying only to FileControls.
+
+    def add_file(self, file_object, content_type=None, filename=None,
+                 name=None, id=None, nr=None):
+        """Add a file to be uploaded.
+
+        file_object: file-like object (with read method) from which to read
+         data to upload
+        content_type: MIME content type of data to upload
+        filename: filename to pass to server
+
+        If filename is None, no filename is sent to the server.
+
+        If content_type is None, the content type is guessed based on the
+        filename and the data from read from the file object.
+
+        XXX
+        At the moment, guessed content type is always application/octet-stream.
+        Use sndhdr, imghdr modules.  Should also try to guess HTML, XML, and
+        plain text.
+
+        """
+        self.find_control(name, "file", id=id, nr=nr).add_file(
+            file_object, content_type, filename)
+
+#---------------------------------------------------
+# Form submission methods, applying only to clickable controls.
+
+    def click(self, name=None, type=None, id=None, nr=0, coord=(1,1)):
+        """Return request that would result from clicking on a control.
+
+        The request object is a urllib2.Request instance, which you can pass to
+        urllib2.urlopen (or ClientCookie.urlopen).
+
+        Only some control types (INPUT/SUBMIT & BUTTON/SUBMIT buttons and
+        IMAGEs) can be clicked.
+
+        Will click on the first clickable control, subject to the name, type
+        and nr arguments (as for find_control).  If no name, type, id or number
+        is specified and there are no clickable controls, a request will be
+        returned for the form in its current, un-clicked, state.
+
+        IndexError is raised if any of name, type, id or nr is specified but no
+        matching control is found.  ValueError is raised if the HTMLForm has an
+        enctype attribute that is not recognised.
+
+        You can optionally specify a coordinate to click at, which only makes a
+        difference if you clicked on an image.
+
+        """
+        return self._click(name, type, id, nr, coord, "request")
+
+    def click_request_data(self,
+                           name=None, type=None, id=None, nr=0, coord=(1,1)):
+        """As for click method, but return a tuple (url, data, headers).
+
+        You can use this data to send a request to the server.  This is useful
+        if you're using httplib or urllib rather than urllib2.  Otherwise, use
+        the click method.
+
+        # Untested.  Have to subclass to add headers, I think -- so use urllib2
+        # instead!
+        import urllib
+        url, data, hdrs = form.click_request_data()
+        r = urllib.urlopen(url, data)
+
+        # Untested.  I don't know of any reason to use httplib -- you can get
+        # just as much control with urllib2.
+        import httplib, urlparse
+        url, data, hdrs = form.click_request_data()
+        tup = urlparse(url)
+        host, path = tup[1], urlparse.urlunparse((None, None)+tup[2:])
+        conn = httplib.HTTPConnection(host)
+        if data:
+            httplib.request("POST", path, data, hdrs)
+        else:
+            httplib.request("GET", path, headers=hdrs)
+        r = conn.getresponse()
+
+        """
+        return self._click(name, type, id, nr, coord, "request_data")
+
+    def click_pairs(self, name=None, type=None, id=None, nr=0, coord=(1,1)):
+        """As for click_request_data, but returns a list of (key, value) pairs.
+
+        You can use this list as an argument to ClientForm.urlencode.  This is
+        usually only useful if you're using httplib or urllib rather than
+        urllib2 or ClientCookie.  It may also be useful if you want to manually
+        tweak the keys and/or values, but this should not be necessary.
+        Otherwise, use the click method.
+
+        Note that this method is only useful for forms of MIME type
+        x-www-form-urlencoded.  In particular, it does not return the
+        information required for file upload.  If you need file upload and are
+        not using urllib2, use click_request_data.
+
+        Also note that Python 2.0's urllib.urlencode is slightly broken: it
+        only accepts a mapping, not a sequence of pairs, as an argument.  This
+        messes up any ordering in the argument.  Use ClientForm.urlencode
+        instead.
+
+        """
+        return self._click(name, type, id, nr, coord, "pairs")
+
+#---------------------------------------------------
+
+    def find_control(self,
+                     name=None, type=None, kind=None, id=None, predicate=None,
+                     nr=None):
+        """Locate some specific control within the form.
+
+        At least one of the name, type, kind, predicate and nr arguments must
+        be supplied.  If no matching control is found, ControlNotFoundError is
+        raised.
+
+        If name is specified, then the control must have the indicated name.
+
+        If type is specified then the control must have the specified type (in
+        addition to the types possible for <input> HTML tags: "text",
+        "password", "hidden", "submit", "image", "button", "radio", "checkbox",
+        "file" we also have "reset", "buttonbutton", "submitbutton",
+        "resetbutton", "textarea", "select" and "isindex").
+
+        If kind is specified, then the control must fall into the specified
+        group, each of which satisfies a particular interface.  The types are
+        "text", "list", "multilist", "singlelist", "clickable" and "file".
+
+        If id is specified, then the control must have the indicated id.
+
+        If predicate is specified, then the control must match that function.
+        The predicate function is passed the control as its single argument,
+        and should return a boolean value indicating whether the control
+        matched.
+
+        nr, if supplied, is the sequence number of the control (where 0 is the
+        first).  Note that control 0 is the first control matching all the
+        other arguments (if supplied); it is not necessarily the first control
+        in the form.
+
+        """
+        if ((name is None) and (type is None) and (kind is None) and
+            (id is None) and (predicate is None) and (nr is None)):
+            raise ValueError(
+                "at least one argument must be supplied to specify control")
+        if nr is None: nr = 0
+
+        return self._find_control(name, type, kind, id, predicate, nr)
+
+#---------------------------------------------------
+# Private methods.
+
+    def _find_list_control(self,
+                           name=None, type=None, kind=None, id=None, nr=None):
+        if ((name is None) and (type is None) and (kind is None) and
+            (id is None) and (nr is None)):
+            raise ValueError(
+                "at least one argument must be supplied to specify control")
+        if nr is None: nr = 0
+
+        return self._find_control(name, type, kind, id, is_listcontrol, nr)
+
+    def _find_control(self, name, type, kind, id, predicate, nr):
+        if (name is not None) and not isstringlike(name):
+            raise TypeError("control name must be string-like")
+        if (type is not None) and not isstringlike(type):
+            raise TypeError("control type must be string-like")
+        if (kind is not None) and not isstringlike(kind):
+            raise TypeError("control kind must be string-like")
+        if (id is not None) and not isstringlike(id):
+            raise TypeError("control id must be string-like")
+        if (predicate is not None) and not callable(predicate):
+            raise TypeError("control predicate must be callable")
+        if nr < 0: raise ValueError("control number must be a positive "
+                                    "integer")
+
+        orig_nr = nr
+
+        for control in self.controls:
+            if name is not None and name != control.name:
+                continue
+            if type is not None and type != control.type:
+                continue
+            if (kind is not None and
+                not self._is_control_in_kind(control, kind)):
+                continue
+            if id is not None and id != control.id:
+                continue
+            if predicate and not predicate(control):
+                continue
+            if nr:
+                nr = nr - 1
+                continue
+            return control
+
+        description = []
+        if name is not None: description.append("name '%s'" % name)
+        if type is not None: description.append("type '%s'" % type)
+        if kind is not None: description.append("kind '%s'" % kind)
+        if id is not None: description.append("id '%s'" % id)
+        if predicate is not None:
+            description.append("matching predicate %s" % predicate)
+        if orig_nr: description.append("nr %d" % orig_nr)
+        description = string.join(description, ", ")
+        raise ControlNotFoundError("no control with "+description)
+
+    def _is_control_in_kind(self, control, kind):
+        # XXX not OO
+        if kind  == "list":
+            return isinstance(control, ListControl)
+        elif kind == "multilist":
+            return bool(isinstance(control, ListControl) and control.multiple)
+        elif kind == "singlelist":
+            return bool(isinstance(control, ListControl) and
+                        not control.multiple)
+        elif kind == "file":
+            return isinstance(control, FileControl)
+        elif kind == "text":
+            return isinstance(control, TextControl)
+        elif kind == "clickable":
+            return (isinstance(control, SubmitControl) or
+                    isinstance(control, IsindexControl))
+        else:
+            raise ValueError("no such control kind '%s'" % kind)
+
+    def _click(self, name, type, id, nr, coord, return_type):
+        try:
+            control = self._find_control(name, type, "clickable", id, None, nr)
+        except ControlNotFoundError:
+            if ((name is not None) or (type is not None) or (id is not None) or
+                (nr != 0)):
+                raise
+            # no clickable controls, but no control was explicitly requested,
+            # so return state without clicking any control
+            return self._switch_click(return_type)
+        else:
+            return control._click(self, coord, return_type)
+
+    def _pairs(self):
+        """Return sequence of (key, value) pairs suitable for urlencoding."""
+        pairs = []
+        for control in self.controls:
+            pairs.extend(control.pairs())
+        return pairs
+
+    def _request_data(self):
+        """Return a tuple (url, data, headers)."""
+        method = string.upper(self.method)
+        if method == "GET":
+            if self.enctype != "application/x-www-form-urlencoded":
+                raise ValueError(
+                    "unknown GET form encoding type '%s'" % self.enctype)
+            uri = "%s?%s" % (self.action, urlencode(self._pairs()))
+            return uri, None, []
+        elif method == "POST":
+            if self.enctype == "application/x-www-form-urlencoded":
+                return (self.action, urlencode(self._pairs()),
+                        [("Content-type", self.enctype)])
+            elif self.enctype == "multipart/form-data":
+                data = StringIO()
+                http_hdrs = []
+                mw = MimeWriter(data, http_hdrs)
+                f = mw.startmultipartbody("form-data", add_to_http_hdrs=True,
+                                          prefix=0)
+                for control in self.controls:
+                    control._write_mime_data(mw)
+                mw.lastpart()
+                return self.action, data.getvalue(), http_hdrs
+            else:
+                raise ValueError(
+                    "unknown POST form encoding type '%s'" % self.enctype)
+        else:
+            raise ValueError("Unknown method '%s'" % method)
+
+    def _switch_click(self, return_type):
+        # This is called by HTMLForm and clickable Controls to hide switching
+        # on return_type.
+        # XXX
+        # not OO
+        # duplicated in IsindexControl._click
+        if return_type == "pairs":
+            return self._pairs()
+        elif return_type == "request_data":
+            return self._request_data()
+        else:
+            req_data = self._request_data()
+            req = urllib2.Request(req_data[0], req_data[1])
+            for key, val in req_data[2]:
+                req.add_header(key, val)
+            return req