diff --git a/Lib/inspect.py b/Lib/inspect.py
index 5c7cfb4..ffe05b7 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -737,9 +737,9 @@
     """Get information about the arguments accepted by a code object.
 
     Three things are returned: (args, varargs, varkw), where
-    'args' is the list of argument names, possibly containing nested
-    lists. Keyword-only arguments are appended. 'varargs' and 'varkw'
-    are the names of the * and ** arguments or None."""
+    'args' is the list of argument names. Keyword-only arguments are
+    appended. 'varargs' and 'varkw' are the names of the * and **
+    arguments or None."""
     args, varargs, kwonlyargs, varkw = _getfullargs(co)
     return Arguments(args + kwonlyargs, varargs, varkw)
 
@@ -747,9 +747,8 @@
     """Get information about the arguments accepted by a code object.
 
     Four things are returned: (args, varargs, kwonlyargs, varkw), where
-    'args' and 'kwonlyargs' are lists of argument names (with 'args'
-    possibly containing nested lists), and 'varargs' and 'varkw' are the
-    names of the * and ** arguments or None."""
+    'args' and 'kwonlyargs' are lists of argument names, and 'varargs'
+    and 'varkw' are the names of the * and ** arguments or None."""
 
     if not iscode(co):
         raise TypeError('{!r} is not a code object'.format(co))
@@ -778,7 +777,7 @@
     """Get the names and default values of a function's arguments.
 
     A tuple of four things is returned: (args, varargs, varkw, defaults).
-    'args' is a list of the argument names (it may contain nested lists).
+    'args' is a list of the argument names.
     'args' will include keyword-only argument names.
     'varargs' and 'varkw' are the names of the * and ** arguments or None.
     'defaults' is an n-tuple of the default values of the last n arguments.
@@ -803,7 +802,7 @@
 
     A tuple of seven things is returned:
     (args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults annotations).
-    'args' is a list of the argument names (it may contain nested lists).
+    'args' is a list of the argument names.
     'varargs' and 'varkw' are the names of the * and ** arguments or None.
     'defaults' is an n-tuple of the default values of the last n arguments.
     'kwonlyargs' is a list of keyword-only argument names.
@@ -827,25 +826,12 @@
     """Get information about arguments passed into a particular frame.
 
     A tuple of four things is returned: (args, varargs, varkw, locals).
-    'args' is a list of the argument names (it may contain nested lists).
+    'args' is a list of the argument names.
     'varargs' and 'varkw' are the names of the * and ** arguments or None.
     'locals' is the locals dictionary of the given frame."""
     args, varargs, varkw = getargs(frame.f_code)
     return ArgInfo(args, varargs, varkw, frame.f_locals)
 
-def joinseq(seq):
-    if len(seq) == 1:
-        return '(' + seq[0] + ',)'
-    else:
-        return '(' + ', '.join(seq) + ')'
-
-def strseq(object, convert, join=joinseq):
-    """Recursively walk a sequence, stringifying each element."""
-    if type(object) in (list, tuple):
-        return join(map(lambda o, c=convert, j=join: strseq(o, c, j), object))
-    else:
-        return convert(object)
-
 def formatannotation(annotation, base_module=None):
     if isinstance(annotation, type):
         if annotation.__module__ in ('builtins', base_module):
@@ -866,8 +852,7 @@
                   formatvarkw=lambda name: '**' + name,
                   formatvalue=lambda value: '=' + repr(value),
                   formatreturns=lambda text: ' -> ' + text,
-                  formatannotation=formatannotation,
-                  join=joinseq):
+                  formatannotation=formatannotation):
     """Format an argument spec from the values returned by getargspec
     or getfullargspec.
 
@@ -885,7 +870,7 @@
     if defaults:
         firstdefault = len(args) - len(defaults)
     for i, arg in enumerate(args):
-        spec = strseq(arg, formatargandannotation, join)
+        spec = formatargandannotation(arg)
         if defaults and i >= firstdefault:
             spec = spec + formatvalue(defaults[i - firstdefault])
         specs.append(spec)
@@ -911,8 +896,7 @@
                     formatarg=str,
                     formatvarargs=lambda name: '*' + name,
                     formatvarkw=lambda name: '**' + name,
-                    formatvalue=lambda value: '=' + repr(value),
-                    join=joinseq):
+                    formatvalue=lambda value: '=' + repr(value)):
     """Format an argument spec from the 4 values returned by getargvalues.
 
     The first four arguments are (args, varargs, varkw, locals).  The
@@ -924,7 +908,7 @@
         return formatarg(name) + formatvalue(locals[name])
     specs = []
     for i in range(len(args)):
-        specs.append(strseq(args[i], convert, join))
+        specs.append(convert(args[i]))
     if varargs:
         specs.append(formatvarargs(varargs) + formatvalue(locals[varargs]))
     if varkw:
diff --git a/Lib/json/__init__.py b/Lib/json/__init__.py
index 5d8cb19..d71c2ce 100644
--- a/Lib/json/__init__.py
+++ b/Lib/json/__init__.py
@@ -155,7 +155,7 @@
 
     To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the
     ``.default()`` method to serialize additional types), specify it with
-    the ``cls`` kwarg.
+    the ``cls`` kwarg; otherwise ``JSONEncoder`` is used.
 
     """
     # cached encoder
@@ -213,7 +213,7 @@
 
     To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the
     ``.default()`` method to serialize additional types), specify it with
-    the ``cls`` kwarg.
+    the ``cls`` kwarg; otherwise ``JSONEncoder`` is used.
 
     """
     # cached encoder
@@ -244,8 +244,16 @@
     ``object_hook`` will be used instead of the ``dict``. This feature
     can be used to implement custom decoders (e.g. JSON-RPC class hinting).
 
+    ``object_pairs_hook`` is an optional function that will be called with the
+    result of any object literal decoded with an ordered list of pairs.  The
+    return value of ``object_pairs_hook`` will be used instead of the ``dict``.
+    This feature can be used to implement custom decoders that rely on the
+    order that the key and value pairs are decoded (for example,
+    collections.OrderedDict will remember the order of insertion). If
+    ``object_hook`` is also defined, the ``object_pairs_hook`` takes priority.
+
     To use a custom ``JSONDecoder`` subclass, specify it with the ``cls``
-    kwarg.
+    kwarg; otherwise ``JSONDecoder`` is used.
 
     """
     return loads(fp.read(),
@@ -264,6 +272,14 @@
     ``object_hook`` will be used instead of the ``dict``. This feature
     can be used to implement custom decoders (e.g. JSON-RPC class hinting).
 
+    ``object_pairs_hook`` is an optional function that will be called with the
+    result of any object literal decoded with an ordered list of pairs.  The
+    return value of ``object_pairs_hook`` will be used instead of the ``dict``.
+    This feature can be used to implement custom decoders that rely on the
+    order that the key and value pairs are decoded (for example,
+    collections.OrderedDict will remember the order of insertion). If
+    ``object_hook`` is also defined, the ``object_pairs_hook`` takes priority.
+
     ``parse_float``, if specified, will be called with the string
     of every JSON float to be decoded. By default this is equivalent to
     float(num_str). This can be used to use another datatype or parser
@@ -280,7 +296,7 @@
     are encountered.
 
     To use a custom ``JSONDecoder`` subclass, specify it with the ``cls``
-    kwarg.
+    kwarg; otherwise ``JSONDecoder`` is used.
 
     """
     if (cls is None and object_hook is None and
diff --git a/Lib/json/decoder.py b/Lib/json/decoder.py
index 3e7405b..d606cbd 100644
--- a/Lib/json/decoder.py
+++ b/Lib/json/decoder.py
@@ -289,6 +289,15 @@
         place of the given ``dict``.  This can be used to provide custom
         deserializations (e.g. to support JSON-RPC class hinting).
 
+        ``object_pairs_hook``, if specified will be called with the result of
+        every JSON object decoded with an ordered list of pairs.  The return
+        value of ``object_pairs_hook`` will be used instead of the ``dict``.
+        This feature can be used to implement custom decoders that rely on the
+        order that the key and value pairs are decoded (for example,
+        collections.OrderedDict will remember the order of insertion). If
+        ``object_hook`` is also defined, the ``object_pairs_hook`` takes
+        priority.
+
         ``parse_float``, if specified, will be called with the string
         of every JSON float to be decoded. By default this is equivalent to
         float(num_str). This can be used to use another datatype or parser
@@ -304,6 +313,11 @@
         This can be used to raise an exception if invalid JSON numbers
         are encountered.
 
+        If ``strict`` is false (true is the default), then control
+        characters will be allowed inside strings.  Control characters in
+        this context are those with character codes in the 0-31 range,
+        including ``'\\t'`` (tab), ``'\\n'``, ``'\\r'`` and ``'\\0'``.
+
         """
         self.object_hook = object_hook
         self.parse_float = parse_float or float
diff --git a/Lib/test/test_minidom.py b/Lib/test/test_minidom.py
index 461ac65..c58d17d 100644
--- a/Lib/test/test_minidom.py
+++ b/Lib/test/test_minidom.py
@@ -1479,6 +1479,13 @@
         doc.appendChild(doc.createComment("foo--bar"))
         self.assertRaises(ValueError, doc.toxml)
 
+    def testEmptyXMLNSValue(self):
+        doc = parseString("<element xmlns=''>\n"
+                          "<foo/>\n</element>")
+        doc2 = parseString(doc.toxml())
+        self.confirm(doc2.namespaceURI == xml.dom.EMPTY_NAMESPACE)
+
+
 def test_main():
     run_unittest(MinidomTest)
 
diff --git a/Lib/xml/dom/minidom.py b/Lib/xml/dom/minidom.py
index f4f4400..0e62e73 100644
--- a/Lib/xml/dom/minidom.py
+++ b/Lib/xml/dom/minidom.py
@@ -293,9 +293,10 @@
 
 def _write_data(writer, data):
     "Writes datachars to writer."
-    data = data.replace("&", "&amp;").replace("<", "&lt;")
-    data = data.replace("\"", "&quot;").replace(">", "&gt;")
-    writer.write(data)
+    if data:
+        data = data.replace("&", "&amp;").replace("<", "&lt;"). \
+                    replace("\"", "&quot;").replace(">", "&gt;")
+        writer.write(data)
 
 def _get_elements_by_tagName_helper(parent, name, rc):
     for node in parent.childNodes:
@@ -1358,11 +1359,9 @@
 class DOMImplementation(DOMImplementationLS):
     _features = [("core", "1.0"),
                  ("core", "2.0"),
-                 ("core", "3.0"),
                  ("core", None),
                  ("xml", "1.0"),
                  ("xml", "2.0"),
-                 ("xml", "3.0"),
                  ("xml", None),
                  ("ls-load", "3.0"),
                  ("ls-load", None),