Move the 2.6 reST doc tree in place.

1 files changed, 1346 insertions, 0 deletions

diff --git a/Doc/library/functions.rst b/Doc/library/functions.rst
new file mode 100644
index 0000000..2f4685d
--- /dev/null
+++ b/Doc/library/functions.rst
@@ -0,0 +1,1346 @@
+
+.. _built-in-funcs:
+
+Built-in Functions
+==================
+
+The Python interpreter has a number of functions built into it that are always
+available.  They are listed here in alphabetical order.
+
+
+.. function:: __import__(name[, globals[, locals[, fromlist[, level]]]])
+
+   .. index::
+      statement: import
+      module: ihooks
+      module: rexec
+      module: imp
+
+   .. note::
+
+      This is an advanced function that is not needed in everyday Python
+      programming.
+
+   The function is invoked by the :keyword:`import` statement.  It mainly exists
+   so that you can replace it with another function that has a compatible
+   interface, in order to change the semantics of the :keyword:`import` statement.
+   For examples of why and how you would do this, see the standard library modules
+   :mod:`ihooks` and :mod:`rexec`.  See also the built-in module :mod:`imp`, which
+   defines some useful operations out of which you can build your own
+   :func:`__import__` function.
+
+   For example, the statement ``import spam`` results in the following call:
+   ``__import__('spam',`` ``globals(),`` ``locals(), [], -1)``; the statement
+   ``from spam.ham import eggs`` results in ``__import__('spam.ham', globals(),
+   locals(), ['eggs'], -1)``.  Note that even though ``locals()`` and ``['eggs']``
+   are passed in as arguments, the :func:`__import__` function does not set the
+   local variable named ``eggs``; this is done by subsequent code that is generated
+   for the import statement.  (In fact, the standard implementation does not use
+   its *locals* argument at all, and uses its *globals* only to determine the
+   package context of the :keyword:`import` statement.)
+
+   When the *name* variable is of the form ``package.module``, normally, the
+   top-level package (the name up till the first dot) is returned, *not* the
+   module named by *name*.  However, when a non-empty *fromlist* argument is
+   given, the module named by *name* is returned.  This is done for
+   compatibility with the bytecode generated for the different kinds of import
+   statement; when using ``import spam.ham.eggs``, the top-level package
+   :mod:`spam` must be placed in the importing namespace, but when using ``from
+   spam.ham import eggs``, the ``spam.ham`` subpackage must be used to find the
+   ``eggs`` variable.  As a workaround for this behavior, use :func:`getattr` to
+   extract the desired components.  For example, you could define the following
+   helper::
+
+      def my_import(name):
+          mod = __import__(name)
+          components = name.split('.')
+          for comp in components[1:]:
+              mod = getattr(mod, comp)
+          return mod
+
+   *level* specifies whether to use absolute or relative imports. The default is
+   ``-1`` which indicates both absolute and relative imports will be attempted.
+   ``0`` means only perform absolute imports. Positive values for *level* indicate
+   the number of parent directories to search relative to the directory of the
+   module calling :func:`__import__`.
+
+   .. versionchanged:: 2.5
+      The level parameter was added.
+
+   .. versionchanged:: 2.5
+      Keyword support for parameters was added.
+
+
+.. function:: abs(x)
+
+   Return the absolute value of a number.  The argument may be a plain or long
+   integer or a floating point number.  If the argument is a complex number, its
+   magnitude is returned.
+
+
+.. function:: all(iterable)
+
+   Return True if all elements of the *iterable* are true. Equivalent to::
+
+      def all(iterable):
+          for element in iterable:
+              if not element:
+                  return False
+          return True
+
+   .. versionadded:: 2.5
+
+
+.. function:: any(iterable)
+
+   Return True if any element of the *iterable* is true. Equivalent to::
+
+      def any(iterable):
+          for element in iterable:
+              if element:
+                  return True
+          return False
+
+   .. versionadded:: 2.5
+
+
+.. function:: basestring()
+
+   This abstract type is the superclass for :class:`str` and :class:`unicode`. It
+   cannot be called or instantiated, but it can be used to test whether an object
+   is an instance of :class:`str` or :class:`unicode`. ``isinstance(obj,
+   basestring)`` is equivalent to ``isinstance(obj, (str, unicode))``.
+
+   .. versionadded:: 2.3
+
+
+.. function:: bool([x])
+
+   Convert a value to a Boolean, using the standard truth testing procedure.  If
+   *x* is false or omitted, this returns :const:`False`; otherwise it returns
+   :const:`True`. :class:`bool` is also a class, which is a subclass of
+   :class:`int`. Class :class:`bool` cannot be subclassed further.  Its only
+   instances are :const:`False` and :const:`True`.
+
+   .. index:: pair: Boolean; type
+
+   .. versionadded:: 2.2.1
+
+   .. versionchanged:: 2.3
+      If no argument is given, this function returns :const:`False`.
+
+
+.. function:: callable(object)
+
+   Return :const:`True` if the *object* argument appears callable,
+   :const:`False` if not.  If this
+   returns true, it is still possible that a call fails, but if it is false,
+   calling *object* will never succeed.  Note that classes are callable (calling a
+   class returns a new instance); class instances are callable if they have a
+   :meth:`__call__` method.
+
+
+.. function:: chr(i)
+
+   Return a string of one character whose ASCII code is the integer *i*.  For
+   example, ``chr(97)`` returns the string ``'a'``. This is the inverse of
+   :func:`ord`.  The argument must be in the range [0..255], inclusive;
+   :exc:`ValueError` will be raised if *i* is outside that range. See
+   also :func:`unichr`.
+
+
+.. function:: classmethod(function)
+
+   Return a class method for *function*.
+
+   A class method receives the class as implicit first argument, just like an
+   instance method receives the instance. To declare a class method, use this
+   idiom::
+
+      class C:
+          @classmethod
+          def f(cls, arg1, arg2, ...): ...
+
+   The ``@classmethod`` form is a function decorator -- see the description of
+   function definitions in :ref:`function` for details.
+
+   It can be called either on the class (such as ``C.f()``) or on an instance (such
+   as ``C().f()``).  The instance is ignored except for its class. If a class
+   method is called for a derived class, the derived class object is passed as the
+   implied first argument.
+
+   Class methods are different than C++ or Java static methods. If you want those,
+   see :func:`staticmethod` in this section.
+
+   For more information on class methods, consult the documentation on the standard
+   type hierarchy in :ref:`types`.
+
+   .. versionadded:: 2.2
+
+   .. versionchanged:: 2.4
+      Function decorator syntax added.
+
+
+.. function:: cmp(x, y)
+
+   Compare the two objects *x* and *y* and return an integer according to the
+   outcome.  The return value is negative if ``x < y``, zero if ``x == y`` and
+   strictly positive if ``x > y``.
+
+
+.. function:: compile(source, filename, mode[, flags[, dont_inherit]])
+
+   Compile the *source* into a code object.  Code objects can be executed by an
+   :keyword:`exec` statement or evaluated by a call to :func:`eval`.  The
+   *filename* argument should give the file from which the code was read; pass some
+   recognizable value if it wasn't read from a file (``'<string>'`` is commonly
+   used). The *mode* argument specifies what kind of code must be compiled; it can
+   be ``'exec'`` if *source* consists of a sequence of statements, ``'eval'`` if it
+   consists of a single expression, or ``'single'`` if it consists of a single
+   interactive statement (in the latter case, expression statements that evaluate
+   to something else than ``None`` will be printed).
+
+   When compiling multi-line statements, two caveats apply: line endings must be
+   represented by a single newline character (``'\n'``), and the input must be
+   terminated by at least one newline character.  If line endings are represented
+   by ``'\r\n'``, use the string :meth:`replace` method to change them into
+   ``'\n'``.
+
+   The optional arguments *flags* and *dont_inherit* (which are new in Python 2.2)
+   control which future statements (see :pep:`236`) affect the compilation of
+   *source*.  If neither is present (or both are zero) the code is compiled with
+   those future statements that are in effect in the code that is calling compile.
+   If the *flags* argument is given and *dont_inherit* is not (or is zero) then the
+   future statements specified by the *flags* argument are used in addition to
+   those that would be used anyway. If *dont_inherit* is a non-zero integer then
+   the *flags* argument is it -- the future statements in effect around the call to
+   compile are ignored.
+
+   Future statements are specified by bits which can be bitwise or-ed together to
+   specify multiple statements.  The bitfield required to specify a given feature
+   can be found as the :attr:`compiler_flag` attribute on the :class:`_Feature`
+   instance in the :mod:`__future__` module.
+
+
+.. function:: complex([real[, imag]])
+
+   Create a complex number with the value *real* + *imag*\*j or convert a string or
+   number to a complex number.  If the first parameter is a string, it will be
+   interpreted as a complex number and the function must be called without a second
+   parameter.  The second parameter can never be a string. Each argument may be any
+   numeric type (including complex). If *imag* is omitted, it defaults to zero and
+   the function serves as a numeric conversion function like :func:`int`,
+   :func:`long` and :func:`float`.  If both arguments are omitted, returns ``0j``.
+
+   The complex type is described in :ref:`typesnumeric`.
+
+
+.. function:: delattr(object, name)
+
+   This is a relative of :func:`setattr`.  The arguments are an object and a
+   string.  The string must be the name of one of the object's attributes.  The
+   function deletes the named attribute, provided the object allows it.  For
+   example, ``delattr(x, 'foobar')`` is equivalent to ``del x.foobar``.
+
+
+.. function:: dict([arg])
+   :noindex:
+
+   Create a new data dictionary, optionally with items taken from *arg*.
+   The dictionary type is described in :ref:`typesmapping`.
+
+   For other containers see the built in :class:`list`, :class:`set`, and
+   :class:`tuple` classes, and the :mod:`collections` module.
+
+
+.. function:: dir([object])
+
+   Without arguments, return the list of names in the current local scope.  With an
+   argument, attempt to return a list of valid attributes for that object.
+
+   If the object has a method named :meth:`__dir__`, this method will be called and
+   must return the list of attributes. This allows objects that implement a custom
+   :func:`__getattr__` or :func:`__getattribute__` function to customize the way
+   :func:`dir` reports their attributes.
+
+   If the object does not provide :meth:`__dir__`, the function tries its best to
+   gather information from the object's :attr:`__dict__` attribute, if defined, and
+   from its type object.  The resulting list is not necessarily complete, and may
+   be inaccurate when the object has a custom :func:`__getattr__`.
+
+   The default :func:`dir` mechanism behaves differently with different types of
+   objects, as it attempts to produce the most relevant, rather than complete,
+   information:
+
+   * If the object is a module object, the list contains the names of the module's
+     attributes.
+
+   * If the object is a type or class object, the list contains the names of its
+     attributes, and recursively of the attributes of its bases.
+
+   * Otherwise, the list contains the object's attributes' names, the names of its
+     class's attributes, and recursively of the attributes of its class's base
+     classes.
+
+   The resulting list is sorted alphabetically.  For example::
+
+      >>> import struct
+      >>> dir()
+      ['__builtins__', '__doc__', '__name__', 'struct']
+      >>> dir(struct)
+      ['__doc__', '__name__', 'calcsize', 'error', 'pack', 'unpack']
+      >>> class Foo(object):
+      ...     def __dir__(self):
+      ...         return ["kan", "ga", "roo"]
+      ...
+      >>> f = Foo()
+      >>> dir(f)
+      ['ga', 'kan', 'roo']
+
+   .. note::
+
+      Because :func:`dir` is supplied primarily as a convenience for use at an
+      interactive prompt, it tries to supply an interesting set of names more than it
+      tries to supply a rigorously or consistently defined set of names, and its
+      detailed behavior may change across releases.
+
+
+.. function:: divmod(a, b)
+
+   Take two (non complex) numbers as arguments and return a pair of numbers
+   consisting of their quotient and remainder when using long division.  With mixed
+   operand types, the rules for binary arithmetic operators apply.  For plain and
+   long integers, the result is the same as ``(a // b, a % b)``. For floating point
+   numbers the result is ``(q, a % b)``, where *q* is usually ``math.floor(a / b)``
+   but may be 1 less than that.  In any case ``q * b + a % b`` is very close to
+   *a*, if ``a % b`` is non-zero it has the same sign as *b*, and ``0 <= abs(a % b)
+   < abs(b)``.
+
+   .. versionchanged:: 2.3
+      Using :func:`divmod` with complex numbers is deprecated.
+
+
+.. function:: enumerate(iterable)
+
+   Return an enumerate object. *iterable* must be a sequence, an iterator, or some
+   other object which supports iteration.  The :meth:`next` method of the iterator
+   returned by :func:`enumerate` returns a tuple containing a count (from zero) and
+   the corresponding value obtained from iterating over *iterable*.
+   :func:`enumerate` is useful for obtaining an indexed series: ``(0, seq[0])``,
+   ``(1, seq[1])``, ``(2, seq[2])``, .... For example::
+
+      >>> for i, season in enumerate(['Spring', 'Summer', 'Fall', 'Winter')]:
+      >>>     print i, season
+      0 Spring
+      1 Summer
+      2 Fall
+      3 Winter
+
+   .. versionadded:: 2.3
+
+
+.. function:: eval(expression[, globals[, locals]])
+
+   The arguments are a string and optional globals and locals.  If provided,
+   *globals* must be a dictionary.  If provided, *locals* can be any mapping
+   object.
+
+   .. versionchanged:: 2.4
+      formerly *locals* was required to be a dictionary.
+
+   The *expression* argument is parsed and evaluated as a Python expression
+   (technically speaking, a condition list) using the *globals* and *locals*
+   dictionaries as global and local name space.  If the *globals* dictionary is
+   present and lacks '__builtins__', the current globals are copied into *globals*
+   before *expression* is parsed.  This means that *expression* normally has full
+   access to the standard :mod:`__builtin__` module and restricted environments are
+   propagated.  If the *locals* dictionary is omitted it defaults to the *globals*
+   dictionary.  If both dictionaries are omitted, the expression is executed in the
+   environment where :keyword:`eval` is called.  The return value is the result of
+   the evaluated expression. Syntax errors are reported as exceptions.  Example::
+
+      >>> x = 1
+      >>> print eval('x+1')
+      2
+
+   This function can also be used to execute arbitrary code objects (such as those
+   created by :func:`compile`).  In this case pass a code object instead of a
+   string.  The code object must have been compiled passing ``'eval'`` as the
+   *kind* argument.
+
+   Hints: dynamic execution of statements is supported by the :keyword:`exec`
+   statement.  Execution of statements from a file is supported by the
+   :func:`execfile` function.  The :func:`globals` and :func:`locals` functions
+   returns the current global and local dictionary, respectively, which may be
+   useful to pass around for use by :func:`eval` or :func:`execfile`.
+
+
+.. function:: execfile(filename[, globals[, locals]])
+
+   This function is similar to the :keyword:`exec` statement, but parses a file
+   instead of a string.  It is different from the :keyword:`import` statement in
+   that it does not use the module administration --- it reads the file
+   unconditionally and does not create a new module. [#]_
+
+   The arguments are a file name and two optional dictionaries.  The file is parsed
+   and evaluated as a sequence of Python statements (similarly to a module) using
+   the *globals* and *locals* dictionaries as global and local namespace. If
+   provided, *locals* can be any mapping object.
+
+   .. versionchanged:: 2.4
+      formerly *locals* was required to be a dictionary.
+
+   If the *locals* dictionary is omitted it defaults to the *globals* dictionary.
+   If both dictionaries are omitted, the expression is executed in the environment
+   where :func:`execfile` is called.  The return value is ``None``.
+
+   .. warning::
+
+      The default *locals* act as described for function :func:`locals` below:
+      modifications to the default *locals* dictionary should not be attempted.  Pass
+      an explicit *locals* dictionary if you need to see effects of the code on
+      *locals* after function :func:`execfile` returns.  :func:`execfile` cannot be
+      used reliably to modify a function's locals.
+
+
+.. function:: file(filename[, mode[, bufsize]])
+
+   Constructor function for the :class:`file` type, described further in section
+   :ref:`bltin-file-objects`.  The constructor's arguments are the same as those
+   of the :func:`open` built-in function described below.
+
+   When opening a file, it's preferable to use :func:`open` instead of  invoking
+   this constructor directly.  :class:`file` is more suited to type testing (for
+   example, writing ``isinstance(f, file)``).
+
+   .. versionadded:: 2.2
+
+
+.. function:: filter(function, iterable)
+
+   Construct a list from those elements of *iterable* for which *function* returns
+   true.  *iterable* may be either a sequence, a container which supports
+   iteration, or an iterator,  If *iterable* is a string or a tuple, the result
+   also has that type; otherwise it is always a list.  If *function* is ``None``,
+   the identity function is assumed, that is, all elements of *iterable* that are
+   false are removed.
+
+   Note that ``filter(function, iterable)`` is equivalent to ``[item for item in
+   iterable if function(item)]`` if function is not ``None`` and ``[item for item
+   in iterable if item]`` if function is ``None``.
+
+
+.. function:: float([x])
+
+   Convert a string or a number to floating point.  If the argument is a string, it
+   must contain a possibly signed decimal or floating point number, possibly
+   embedded in whitespace. Otherwise, the argument may be a plain or long integer
+   or a floating point number, and a floating point number with the same value
+   (within Python's floating point precision) is returned.  If no argument is
+   given, returns ``0.0``.
+
+   .. note::
+
+      .. index::
+         single: NaN
+         single: Infinity
+
+      When passing in a string, values for NaN and Infinity may be returned, depending
+      on the underlying C library.  The specific set of strings accepted which cause
+      these values to be returned depends entirely on the C library and is known to
+      vary.
+
+   The float type is described in :ref:`typesnumeric`.
+
+.. function:: frozenset([iterable])
+   :noindex:
+
+   Return a frozenset object, optionally with elements taken from *iterable*.
+   The frozenset type is described in :ref:`types-set`.
+
+   For other containers see the built in :class:`dict`, :class:`list`, and
+   :class:`tuple` classes, and the :mod:`collections` module.
+
+   .. versionadded:: 2.4
+
+
+.. function:: getattr(object, name[, default])
+
+   Return the value of the named attributed of *object*.  *name* must be a string.
+   If the string is the name of one of the object's attributes, the result is the
+   value of that attribute.  For example, ``getattr(x, 'foobar')`` is equivalent to
+   ``x.foobar``.  If the named attribute does not exist, *default* is returned if
+   provided, otherwise :exc:`AttributeError` is raised.
+
+
+.. function:: globals()
+
+   Return a dictionary representing the current global symbol table. This is always
+   the dictionary of the current module (inside a function or method, this is the
+   module where it is defined, not the module from which it is called).
+
+
+.. function:: hasattr(object, name)
+
+   The arguments are an object and a string.  The result is ``True`` if the string
+   is the name of one of the object's attributes, ``False`` if not. (This is
+   implemented by calling ``getattr(object, name)`` and seeing whether it raises an
+   exception or not.)
+
+
+.. function:: hash(object)
+
+   Return the hash value of the object (if it has one).  Hash values are integers.
+   They are used to quickly compare dictionary keys during a dictionary lookup.
+   Numeric values that compare equal have the same hash value (even if they are of
+   different types, as is the case for 1 and 1.0).
+
+
+.. function:: help([object])
+
+   Invoke the built-in help system.  (This function is intended for interactive
+   use.)  If no argument is given, the interactive help system starts on the
+   interpreter console.  If the argument is a string, then the string is looked up
+   as the name of a module, function, class, method, keyword, or documentation
+   topic, and a help page is printed on the console.  If the argument is any other
+   kind of object, a help page on the object is generated.
+
+   .. versionadded:: 2.2
+
+
+.. function:: hex(x)
+
+   Convert an integer number (of any size) to a hexadecimal string. The result is a
+   valid Python expression.
+
+   .. versionchanged:: 2.4
+      Formerly only returned an unsigned literal.
+
+
+.. function:: id(object)
+
+   Return the "identity" of an object.  This is an integer (or long integer) which
+   is guaranteed to be unique and constant for this object during its lifetime.
+   Two objects with non-overlapping lifetimes may have the same :func:`id` value.
+   (Implementation note: this is the address of the object.)
+
+
+.. function:: input([prompt])
+
+   Equivalent to ``eval(raw_input(prompt))``.
+
+   .. warning::
+
+      This function is not safe from user errors!  It expects a valid Python
+      expression as input; if the input is not syntactically valid, a
+      :exc:`SyntaxError` will be raised. Other exceptions may be raised if there is an
+      error during evaluation.  (On the other hand, sometimes this is exactly what you
+      need when writing a quick script for expert use.)
+
+   If the :mod:`readline` module was loaded, then :func:`input` will use it to
+   provide elaborate line editing and history features.
+
+   Consider using the :func:`raw_input` function for general input from users.
+
+
+.. function:: int([x[, radix]])
+
+   Convert a string or number to a plain integer.  If the argument is a string, it
+   must contain a possibly signed decimal number representable as a Python integer,
+   possibly embedded in whitespace. The *radix* parameter gives the base for the
+   conversion and may be any integer in the range [2, 36], or zero.  If *radix* is
+   zero, the proper radix is guessed based on the contents of string; the
+   interpretation is the same as for integer literals.  If *radix* is specified and
+   *x* is not a string, :exc:`TypeError` is raised. Otherwise, the argument may be
+   a plain or long integer or a floating point number.  Conversion of floating
+   point numbers to integers truncates (towards zero). If the argument is outside
+   the integer range a long object will be returned instead.  If no arguments are
+   given, returns ``0``.
+
+   The integer type is described in :ref:`typesnumeric`.
+
+
+.. function:: isinstance(object, classinfo)
+
+   Return true if the *object* argument is an instance of the *classinfo* argument,
+   or of a (direct or indirect) subclass thereof.  Also return true if *classinfo*
+   is a type object (new-style class) and *object* is an object of that type or of
+   a (direct or indirect) subclass thereof.  If *object* is not a class instance or
+   an object of the given type, the function always returns false.  If *classinfo*
+   is neither a class object nor a type object, it may be a tuple of class or type
+   objects, or may recursively contain other such tuples (other sequence types are
+   not accepted).  If *classinfo* is not a class, type, or tuple of classes, types,
+   and such tuples, a :exc:`TypeError` exception is raised.
+
+   .. versionchanged:: 2.2
+      Support for a tuple of type information was added.
+
+
+.. function:: issubclass(class, classinfo)
+
+   Return true if *class* is a subclass (direct or indirect) of *classinfo*.  A
+   class is considered a subclass of itself. *classinfo* may be a tuple of class
+   objects, in which case every entry in *classinfo* will be checked. In any other
+   case, a :exc:`TypeError` exception is raised.
+
+   .. versionchanged:: 2.3
+      Support for a tuple of type information was added.
+
+
+.. function:: iter(o[, sentinel])
+
+   Return an iterator object.  The first argument is interpreted very differently
+   depending on the presence of the second argument. Without a second argument, *o*
+   must be a collection object which supports the iteration protocol (the
+   :meth:`__iter__` method), or it must support the sequence protocol (the
+   :meth:`__getitem__` method with integer arguments starting at ``0``).  If it
+   does not support either of those protocols, :exc:`TypeError` is raised. If the
+   second argument, *sentinel*, is given, then *o* must be a callable object.  The
+   iterator created in this case will call *o* with no arguments for each call to
+   its :meth:`next` method; if the value returned is equal to *sentinel*,
+   :exc:`StopIteration` will be raised, otherwise the value will be returned.
+
+   .. versionadded:: 2.2
+
+
+.. function:: len(s)
+
+   Return the length (the number of items) of an object.  The argument may be a
+   sequence (string, tuple or list) or a mapping (dictionary).
+
+
+.. function:: list([iterable])
+
+   Return a list whose items are the same and in the same order as *iterable*'s
+   items.  *iterable* may be either a sequence, a container that supports
+   iteration, or an iterator object.  If *iterable* is already a list, a copy is
+   made and returned, similar to ``iterable[:]``.  For instance, ``list('abc')``
+   returns ``['a', 'b', 'c']`` and ``list( (1, 2, 3) )`` returns ``[1, 2, 3]``.  If
+   no argument is given, returns a new empty list, ``[]``.
+
+   :class:`list` is a mutable sequence type, as documented in
+   :ref:`typesseq`. For other containers see the built in :class:`dict`,
+   :class:`set`, and :class:`tuple` classes, and the :mod:`collections` module.
+
+
+.. function:: locals()
+
+   Update and return a dictionary representing the current local symbol table.
+
+   .. warning::
+
+      The contents of this dictionary should not be modified; changes may not affect
+      the values of local variables used by the interpreter.
+
+   Free variables are returned by *locals* when it is called in a function block.
+   Modifications of free variables may not affect the values used by the
+   interpreter.  Free variables are not returned in class blocks.
+
+
+.. function:: long([x[, radix]])
+
+   Convert a string or number to a long integer.  If the argument is a string, it
+   must contain a possibly signed number of arbitrary size, possibly embedded in
+   whitespace. The *radix* argument is interpreted in the same way as for
+   :func:`int`, and may only be given when *x* is a string. Otherwise, the argument
+   may be a plain or long integer or a floating point number, and a long integer
+   with the same value is returned.    Conversion of floating point numbers to
+   integers truncates (towards zero).  If no arguments are given, returns ``0L``.
+
+   The long type is described in :ref:`typesnumeric`.
+
+.. function:: map(function, iterable, ...)
+
+   Apply *function* to every item of *iterable* and return a list of the results.
+   If additional *iterable* arguments are passed, *function* must take that many
+   arguments and is applied to the items from all iterables in parallel.  If one
+   iterable is shorter than another it is assumed to be extended with ``None``
+   items.  If *function* is ``None``, the identity function is assumed; if there
+   are multiple arguments, :func:`map` returns a list consisting of tuples
+   containing the corresponding items from all iterables (a kind of transpose
+   operation).  The *iterable* arguments may be a sequence  or any iterable object;
+   the result is always a list.
+
+
+.. function:: max(iterable[, args...][key])
+
+   With a single argument *iterable*, return the largest item of a non-empty
+   iterable (such as a string, tuple or list).  With more than one argument, return
+   the largest of the arguments.
+
+   The optional *key* argument specifies a one-argument ordering function like that
+   used for :meth:`list.sort`.  The *key* argument, if supplied, must be in keyword
+   form (for example, ``max(a,b,c,key=func)``).
+
+   .. versionchanged:: 2.5
+      Added support for the optional *key* argument.
+
+
+.. function:: min(iterable[, args...][key])
+
+   With a single argument *iterable*, return the smallest item of a non-empty
+   iterable (such as a string, tuple or list).  With more than one argument, return
+   the smallest of the arguments.
+
+   The optional *key* argument specifies a one-argument ordering function like that
+   used for :meth:`list.sort`.  The *key* argument, if supplied, must be in keyword
+   form (for example, ``min(a,b,c,key=func)``).
+
+   .. versionchanged:: 2.5
+      Added support for the optional *key* argument.
+
+
+.. function:: object()
+
+   Return a new featureless object.  :class:`object` is a base for all new style
+   classes.  It has the methods that are common to all instances of new style
+   classes.
+
+   .. versionadded:: 2.2
+
+   .. versionchanged:: 2.3
+      This function does not accept any arguments. Formerly, it accepted arguments but
+      ignored them.
+
+
+.. function:: oct(x)
+
+   Convert an integer number (of any size) to an octal string.  The result is a
+   valid Python expression.
+
+   .. versionchanged:: 2.4
+      Formerly only returned an unsigned literal.
+
+
+.. function:: open(filename[, mode[, bufsize]])
+
+   Open a file, returning an object of the :class:`file` type described in
+   section :ref:`bltin-file-objects`.  If the file cannot be opened,
+   :exc:`IOError` is raised.  When opening a file, it's preferable to use
+   :func:`open` instead of invoking the :class:`file` constructor directly.
+
+   The first two arguments are the same as for ``stdio``'s :cfunc:`fopen`:
+   *filename* is the file name to be opened, and *mode* is a string indicating how
+   the file is to be opened.
+
+   The most commonly-used values of *mode* are ``'r'`` for reading, ``'w'`` for
+   writing (truncating the file if it already exists), and ``'a'`` for appending
+   (which on *some* Unix systems means that *all* writes append to the end of the
+   file regardless of the current seek position).  If *mode* is omitted, it
+   defaults to ``'r'``.  When opening a binary file, you should append ``'b'`` to
+   the *mode* value to open the file in binary mode, which will improve
+   portability.  (Appending ``'b'`` is useful even on systems that don't treat
+   binary and text files differently, where it serves as documentation.)  See below
+   for more possible values of *mode*.
+
+   .. index::
+      single: line-buffered I/O
+      single: unbuffered I/O
+      single: buffer size, I/O
+      single: I/O control; buffering
+
+   The optional *bufsize* argument specifies the file's desired buffer size: 0
+   means unbuffered, 1 means line buffered, any other positive value means use a
+   buffer of (approximately) that size.  A negative *bufsize* means to use the
+   system default, which is usually line buffered for tty devices and fully
+   buffered for other files.  If omitted, the system default is used. [#]_
+
+   Modes ``'r+'``, ``'w+'`` and ``'a+'`` open the file for updating (note that
+   ``'w+'`` truncates the file).  Append ``'b'`` to the mode to open the file in
+   binary mode, on systems that differentiate between binary and text files; on
+   systems that don't have this distinction, adding the ``'b'`` has no effect.
+
+   In addition to the standard :cfunc:`fopen` values *mode* may be ``'U'`` or
+   ``'rU'``.  Python is usually built with universal newline support; supplying
+   ``'U'`` opens the file as a text file, but lines may be terminated by any of the
+   following: the Unix end-of-line convention ``'\n'``,  the Macintosh convention
+   ``'\r'``, or the Windows convention ``'\r\n'``. All of these external
+   representations are seen as ``'\n'`` by the Python program. If Python is built
+   without universal newline support a *mode* with ``'U'`` is the same as normal
+   text mode.  Note that file objects so opened also have an attribute called
+   :attr:`newlines` which has a value of ``None`` (if no newlines have yet been
+   seen), ``'\n'``, ``'\r'``, ``'\r\n'``, or a tuple containing all the newline
+   types seen.
+
+   Python enforces that the mode, after stripping ``'U'``, begins with ``'r'``,
+   ``'w'`` or ``'a'``.
+
+   See also the :mod:`fileinput` module.
+
+   .. versionchanged:: 2.5
+      Restriction on first letter of mode string introduced.
+
+
+.. function:: ord(c)
+
+   Given a string of length one, return an integer representing the Unicode code
+   point of the character when the argument is a unicode object, or the value of
+   the byte when the argument is an 8-bit string. For example, ``ord('a')`` returns
+   the integer ``97``, ``ord(u'\u2020')`` returns ``8224``.  This is the inverse of
+   :func:`chr` for 8-bit strings and of :func:`unichr` for unicode objects.  If a
+   unicode argument is given and Python was built with UCS2 Unicode, then the
+   character's code point must be in the range [0..65535] inclusive; otherwise the
+   string length is two, and a :exc:`TypeError` will be raised.
+
+
+.. function:: pow(x, y[, z])
+
+   Return *x* to the power *y*; if *z* is present, return *x* to the power *y*,
+   modulo *z* (computed more efficiently than ``pow(x, y) % z``). The two-argument
+   form ``pow(x, y)`` is equivalent to using the power operator: ``x**y``.
+
+   The arguments must have numeric types.  With mixed operand types, the coercion
+   rules for binary arithmetic operators apply.  For int and long int operands, the
+   result has the same type as the operands (after coercion) unless the second
+   argument is negative; in that case, all arguments are converted to float and a
+   float result is delivered.  For example, ``10**2`` returns ``100``, but
+   ``10**-2`` returns ``0.01``.  (This last feature was added in Python 2.2.  In
+   Python 2.1 and before, if both arguments were of integer types and the second
+   argument was negative, an exception was raised.) If the second argument is
+   negative, the third argument must be omitted. If *z* is present, *x* and *y*
+   must be of integer types, and *y* must be non-negative.  (This restriction was
+   added in Python 2.2.  In Python 2.1 and before, floating 3-argument ``pow()``
+   returned platform-dependent results depending on floating-point rounding
+   accidents.)
+
+
+.. function:: property([fget[, fset[, fdel[, doc]]]])
+
+   Return a property attribute for new-style classes (classes that derive from
+   :class:`object`).
+
+   *fget* is a function for getting an attribute value, likewise *fset* is a
+   function for setting, and *fdel* a function for del'ing, an attribute.  Typical
+   use is to define a managed attribute x::
+
+      class C(object):
+          def __init__(self): self._x = None
+          def getx(self): return self._x
+          def setx(self, value): self._x = value
+          def delx(self): del self._x
+          x = property(getx, setx, delx, "I'm the 'x' property.")
+
+   If given, *doc* will be the docstring of the property attribute. Otherwise, the
+   property will copy *fget*'s docstring (if it exists).  This makes it possible to
+   create read-only properties easily using :func:`property` as a decorator::
+
+      class Parrot(object):
+          def __init__(self):
+              self._voltage = 100000
+
+          @property
+          def voltage(self):
+              """Get the current voltage."""
+              return self._voltage
+
+   turns the :meth:`voltage` method into a "getter" for a read-only attribute with
+   the same name.
+
+   .. versionadded:: 2.2
+
+   .. versionchanged:: 2.5
+      Use *fget*'s docstring if no *doc* given.
+
+
+.. function:: range([start,] stop[, step])
+
+   This is a versatile function to create lists containing arithmetic progressions.
+   It is most often used in :keyword:`for` loops.  The arguments must be plain
+   integers.  If the *step* argument is omitted, it defaults to ``1``.  If the
+   *start* argument is omitted, it defaults to ``0``.  The full form returns a list
+   of plain integers ``[start, start + step, start + 2 * step, ...]``.  If *step*
+   is positive, the last element is the largest ``start + i * step`` less than
+   *stop*; if *step* is negative, the last element is the smallest ``start + i *
+   step`` greater than *stop*.  *step* must not be zero (or else :exc:`ValueError`
+   is raised).  Example::
+
+      >>> range(10)
+      [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
+      >>> range(1, 11)
+      [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+      >>> range(0, 30, 5)
+      [0, 5, 10, 15, 20, 25]
+      >>> range(0, 10, 3)
+      [0, 3, 6, 9]
+      >>> range(0, -10, -1)
+      [0, -1, -2, -3, -4, -5, -6, -7, -8, -9]
+      >>> range(0)
+      []
+      >>> range(1, 0)
+      []
+
+
+.. function:: raw_input([prompt])
+
+   If the *prompt* argument is present, it is written to standard output without a
+   trailing newline.  The function then reads a line from input, converts it to a
+   string (stripping a trailing newline), and returns that. When EOF is read,
+   :exc:`EOFError` is raised. Example::
+
+      >>> s = raw_input('--> ')
+      --> Monty Python's Flying Circus
+      >>> s
+      "Monty Python's Flying Circus"
+
+   If the :mod:`readline` module was loaded, then :func:`raw_input` will use it to
+   provide elaborate line editing and history features.
+
+
+.. function:: reduce(function, iterable[, initializer])
+
+   Apply *function* of two arguments cumulatively to the items of *iterable*, from
+   left to right, so as to reduce the iterable to a single value.  For example,
+   ``reduce(lambda x, y: x+y, [1, 2, 3, 4, 5])`` calculates ``((((1+2)+3)+4)+5)``.
+   The left argument, *x*, is the accumulated value and the right argument, *y*, is
+   the update value from the *iterable*.  If the optional *initializer* is present,
+   it is placed before the items of the iterable in the calculation, and serves as
+   a default when the iterable is empty.  If *initializer* is not given and
+   *iterable* contains only one item, the first item is returned.
+
+
+.. function:: reload(module)
+
+   Reload a previously imported *module*.  The argument must be a module object, so
+   it must have been successfully imported before.  This is useful if you have
+   edited the module source file using an external editor and want to try out the
+   new version without leaving the Python interpreter.  The return value is the
+   module object (the same as the *module* argument).
+
+   When ``reload(module)`` is executed:
+
+   * Python modules' code is recompiled and the module-level code reexecuted,
+     defining a new set of objects which are bound to names in the module's
+     dictionary.  The ``init`` function of extension modules is not called a second
+     time.
+
+   * As with all other objects in Python the old objects are only reclaimed after
+     their reference counts drop to zero.
+
+   * The names in the module namespace are updated to point to any new or changed
+     objects.
+
+   * Other references to the old objects (such as names external to the module) are
+     not rebound to refer to the new objects and must be updated in each namespace
+     where they occur if that is desired.
+
+   There are a number of other caveats:
+
+   If a module is syntactically correct but its initialization fails, the first
+   :keyword:`import` statement for it does not bind its name locally, but does
+   store a (partially initialized) module object in ``sys.modules``.  To reload the
+   module you must first :keyword:`import` it again (this will bind the name to the
+   partially initialized module object) before you can :func:`reload` it.
+
+   When a module is reloaded, its dictionary (containing the module's global
+   variables) is retained.  Redefinitions of names will override the old
+   definitions, so this is generally not a problem.  If the new version of a module
+   does not define a name that was defined by the old version, the old definition
+   remains.  This feature can be used to the module's advantage if it maintains a
+   global table or cache of objects --- with a :keyword:`try` statement it can test
+   for the table's presence and skip its initialization if desired::
+
+      try:
+          cache
+      except NameError:
+          cache = {}
+
+   It is legal though generally not very useful to reload built-in or dynamically
+   loaded modules, except for :mod:`sys`, :mod:`__main__` and :mod:`__builtin__`.
+   In many cases, however, extension modules are not designed to be initialized
+   more than once, and may fail in arbitrary ways when reloaded.
+
+   If a module imports objects from another module using :keyword:`from` ...
+   :keyword:`import` ..., calling :func:`reload` for the other module does not
+   redefine the objects imported from it --- one way around this is to re-execute
+   the :keyword:`from` statement, another is to use :keyword:`import` and qualified
+   names (*module*.*name*) instead.
+
+   If a module instantiates instances of a class, reloading the module that defines
+   the class does not affect the method definitions of the instances --- they
+   continue to use the old class definition.  The same is true for derived classes.
+
+
+.. function:: repr(object)
+
+   Return a string containing a printable representation of an object. This is the
+   same value yielded by conversions (reverse quotes). It is sometimes useful to be
+   able to access this operation as an ordinary function.  For many types, this
+   function makes an attempt to return a string that would yield an object with the
+   same value when passed to :func:`eval`.
+
+
+.. function:: reversed(seq)
+
+   Return a reverse iterator.  *seq* must be an object which supports the sequence
+   protocol (the :meth:`__len__` method and the :meth:`__getitem__` method with
+   integer arguments starting at ``0``).
+
+   .. versionadded:: 2.4
+
+
+.. function:: round(x[, n])
+
+   Return the floating point value *x* rounded to *n* digits after the decimal
+   point.  If *n* is omitted, it defaults to zero. The result is a floating point
+   number.  Values are rounded to the closest multiple of 10 to the power minus
+   *n*; if two multiples are equally close, rounding is done away from 0 (so. for
+   example, ``round(0.5)`` is ``1.0`` and ``round(-0.5)`` is ``-1.0``).
+
+
+.. function:: set([iterable])
+   :noindex:
+
+   Return a new set, optionally with elements are taken from *iterable*.
+   The set type is described in :ref:`types-set`.
+
+   For other containers see the built in :class:`dict`, :class:`list`, and
+   :class:`tuple` classes, and the :mod:`collections` module.
+
+   .. versionadded:: 2.4
+
+
+.. function:: setattr(object, name, value)
+
+   This is the counterpart of :func:`getattr`.  The arguments are an object, a
+   string and an arbitrary value.  The string may name an existing attribute or a
+   new attribute.  The function assigns the value to the attribute, provided the
+   object allows it.  For example, ``setattr(x, 'foobar', 123)`` is equivalent to
+   ``x.foobar = 123``.
+
+
+.. function:: slice([start,] stop[, step])
+
+   .. index:: single: Numerical Python
+
+   Return a slice object representing the set of indices specified by
+   ``range(start, stop, step)``.  The *start* and *step* arguments default to
+   ``None``.  Slice objects have read-only data attributes :attr:`start`,
+   :attr:`stop` and :attr:`step` which merely return the argument values (or their
+   default).  They have no other explicit functionality; however they are used by
+   Numerical Python and other third party extensions.  Slice objects are also
+   generated when extended indexing syntax is used.  For example:
+   ``a[start:stop:step]`` or ``a[start:stop, i]``.
+
+
+.. function:: sorted(iterable[, cmp[, key[, reverse]]])
+
+   Return a new sorted list from the items in *iterable*.
+
+   The optional arguments *cmp*, *key*, and *reverse* have the same meaning as
+   those for the :meth:`list.sort` method (described in section
+   :ref:`typesseq-mutable`).
+
+   *cmp* specifies a custom comparison function of two arguments (iterable
+   elements) which should return a negative, zero or positive number depending on
+   whether the first argument is considered smaller than, equal to, or larger than
+   the second argument: ``cmp=lambda x,y: cmp(x.lower(), y.lower())``
+
+   *key* specifies a function of one argument that is used to extract a comparison
+   key from each list element: ``key=str.lower``
+
+   *reverse* is a boolean value.  If set to ``True``, then the list elements are
+   sorted as if each comparison were reversed.
+
+   In general, the *key* and *reverse* conversion processes are much faster than
+   specifying an equivalent *cmp* function.  This is because *cmp* is called
+   multiple times for each list element while *key* and *reverse* touch each
+   element only once.
+
+   .. versionadded:: 2.4
+
+
+.. function:: staticmethod(function)
+
+   Return a static method for *function*.
+
+   A static method does not receive an implicit first argument. To declare a static
+   method, use this idiom::
+
+      class C:
+          @staticmethod
+          def f(arg1, arg2, ...): ...
+
+   The ``@staticmethod`` form is a function decorator -- see the description of
+   function definitions in :ref:`function` for details.
+
+   It can be called either on the class (such as ``C.f()``) or on an instance (such
+   as ``C().f()``).  The instance is ignored except for its class.
+
+   Static methods in Python are similar to those found in Java or C++. For a more
+   advanced concept, see :func:`classmethod` in this section.
+
+   For more information on static methods, consult the documentation on the
+   standard type hierarchy in :ref:`types`.
+
+   .. versionadded:: 2.2
+
+   .. versionchanged:: 2.4
+      Function decorator syntax added.
+
+
+.. function:: str([object])
+
+   Return a string containing a nicely printable representation of an object.  For
+   strings, this returns the string itself.  The difference with ``repr(object)``
+   is that ``str(object)`` does not always attempt to return a string that is
+   acceptable to :func:`eval`; its goal is to return a printable string.  If no
+   argument is given, returns the empty string, ``''``.
+
+   For more information on strings see :ref:`typesseq` which describes sequence
+   functionality (strings are sequences), and also the string-specific methods
+   described in the :ref:`string-methods` section. To output formatted strings
+   use template strings or the ``%`` operator described in the
+   :ref:`string-formatting` section. In addition see the :ref:`stringservices`
+   section. See also :func:`unicode`.
+
+
+.. function:: sum(iterable[, start])
+
+   Sums *start* and the items of an *iterable* from left to right and returns the
+   total.  *start* defaults to ``0``. The *iterable*'s items are normally numbers,
+   and are not allowed to be strings.  The fast, correct way to concatenate a
+   sequence of strings is by calling ``''.join(sequence)``. Note that
+   ``sum(range(n), m)`` is equivalent to ``reduce(operator.add, range(n), m)``
+
+   .. versionadded:: 2.3
+
+
+.. function:: super(type[, object-or-type])
+
+   Return the superclass of *type*.  If the second argument is omitted the super
+   object returned is unbound.  If the second argument is an object,
+   ``isinstance(obj, type)`` must be true.  If the second argument is a type,
+   ``issubclass(type2, type)`` must be true. :func:`super` only works for new-style
+   classes.
+
+   A typical use for calling a cooperative superclass method is::
+
+      class C(B):
+          def meth(self, arg):
+              super(C, self).meth(arg)
+
+   Note that :func:`super` is implemented as part of the binding process for
+   explicit dotted attribute lookups such as ``super(C, self).__getitem__(name)``.
+   Accordingly, :func:`super` is undefined for implicit lookups using statements or
+   operators such as ``super(C, self)[name]``.
+
+   .. versionadded:: 2.2
+
+
+.. function:: tuple([iterable])
+
+   Return a tuple whose items are the same and in the same order as *iterable*'s
+   items.  *iterable* may be a sequence, a container that supports iteration, or an
+   iterator object. If *iterable* is already a tuple, it is returned unchanged.
+   For instance, ``tuple('abc')`` returns ``('a', 'b', 'c')`` and ``tuple([1, 2,
+   3])`` returns ``(1, 2, 3)``.  If no argument is given, returns a new empty
+   tuple, ``()``.
+
+   :class:`tuple` is an immutable sequence type, as documented in
+   :ref:`typesseq`. For other containers see the built in :class:`dict`,
+   :class:`list`, and :class:`set` classes, and the :mod:`collections` module.
+
+
+.. function:: type(object)
+
+   .. index:: object: type
+
+   Return the type of an *object*.  The return value is a type object.  The
+   :func:`isinstance` built-in function is recommended for testing the type of an
+   object.
+
+   With three arguments, :func:`type` functions as a constructor as detailed below.
+
+
+.. function:: type(name, bases, dict)
+   :noindex:
+
+   Return a new type object.  This is essentially a dynamic form of the
+   :keyword:`class` statement. The *name* string is the class name and becomes the
+   :attr:`__name__` attribute; the *bases* tuple itemizes the base classes and
+   becomes the :attr:`__bases__` attribute; and the *dict* dictionary is the
+   namespace containing definitions for class body and becomes the :attr:`__dict__`
+   attribute.  For example, the following two statements create identical
+   :class:`type` objects::
+
+      >>> class X(object):
+      ...     a = 1
+      ...     
+      >>> X = type('X', (object,), dict(a=1))
+
+   .. versionadded:: 2.2
+
+
+.. function:: unichr(i)
+
+   Return the Unicode string of one character whose Unicode code is the integer
+   *i*.  For example, ``unichr(97)`` returns the string ``u'a'``.  This is the
+   inverse of :func:`ord` for Unicode strings.  The valid range for the argument
+   depends how Python was configured -- it may be either UCS2 [0..0xFFFF] or UCS4
+   [0..0x10FFFF]. :exc:`ValueError` is raised otherwise. For ASCII and 8-bit
+   strings see :func:`chr`.
+
+   .. versionadded:: 2.0
+
+
+.. function:: unicode([object[, encoding [, errors]]])
+
+   Return the Unicode string version of *object* using one of the following modes:
+
+   If *encoding* and/or *errors* are given, ``unicode()`` will decode the object
+   which can either be an 8-bit string or a character buffer using the codec for
+   *encoding*. The *encoding* parameter is a string giving the name of an encoding;
+   if the encoding is not known, :exc:`LookupError` is raised. Error handling is
+   done according to *errors*; this specifies the treatment of characters which are
+   invalid in the input encoding.  If *errors* is ``'strict'`` (the default), a
+   :exc:`ValueError` is raised on errors, while a value of ``'ignore'`` causes
+   errors to be silently ignored, and a value of ``'replace'`` causes the official
+   Unicode replacement character, ``U+FFFD``, to be used to replace input
+   characters which cannot be decoded.  See also the :mod:`codecs` module.
+
+   If no optional parameters are given, ``unicode()`` will mimic the behaviour of
+   ``str()`` except that it returns Unicode strings instead of 8-bit strings. More
+   precisely, if *object* is a Unicode string or subclass it will return that
+   Unicode string without any additional decoding applied.
+
+   For objects which provide a :meth:`__unicode__` method, it will call this method
+   without arguments to create a Unicode string. For all other objects, the 8-bit
+   string version or representation is requested and then converted to a Unicode
+   string using the codec for the default encoding in ``'strict'`` mode.
+
+   For more information on Unicode strings see :ref:`typesseq` which describes
+   sequence functionality (Unicode strings are sequences), and also the
+   string-specific methods described in the :ref:`string-methods` section. To
+   output formatted strings use template strings or the ``%`` operator described
+   in the :ref:`string-formatting` section. In addition see the
+   :ref:`stringservices` section. See also :func:`str`.
+
+   .. versionadded:: 2.0
+
+   .. versionchanged:: 2.2
+      Support for :meth:`__unicode__` added.
+
+
+.. function:: vars([object])
+
+   Without arguments, return a dictionary corresponding to the current local symbol
+   table.  With a module, class or class instance object as argument (or anything
+   else that has a :attr:`__dict__` attribute), returns a dictionary corresponding
+   to the object's symbol table.  The returned dictionary should not be modified:
+   the effects on the corresponding symbol table are undefined. [#]_
+
+
+.. function:: xrange([start,] stop[, step])
+
+   This function is very similar to :func:`range`, but returns an "xrange object"
+   instead of a list.  This is an opaque sequence type which yields the same values
+   as the corresponding list, without actually storing them all simultaneously.
+   The advantage of :func:`xrange` over :func:`range` is minimal (since
+   :func:`xrange` still has to create the values when asked for them) except when a
+   very large range is used on a memory-starved machine or when all of the range's
+   elements are never used (such as when the loop is usually terminated with
+   :keyword:`break`).
+
+   .. note::
+
+      :func:`xrange` is intended to be simple and fast. Implementations may impose
+      restrictions to achieve this. The C implementation of Python restricts all
+      arguments to native C longs ("short" Python integers), and also requires that
+      the number of elements fit in a native C long.
+
+
+.. function:: zip([iterable, ...])
+
+   This function returns a list of tuples, where the *i*-th tuple contains the
+   *i*-th element from each of the argument sequences or iterables. The returned
+   list is truncated in length to the length of the shortest argument sequence.
+   When there are multiple arguments which are all of the same length, :func:`zip`
+   is similar to :func:`map` with an initial argument of ``None``. With a single
+   sequence argument, it returns a list of 1-tuples. With no arguments, it returns
+   an empty list.
+
+   .. versionadded:: 2.0
+
+   .. versionchanged:: 2.4
+      Formerly, :func:`zip` required at least one argument and ``zip()`` raised a
+      :exc:`TypeError` instead of returning an empty list.
+
+.. % ---------------------------------------------------------------------------
+
+
+.. _non-essential-built-in-funcs:
+
+Non-essential Built-in Functions
+================================
+
+There are several built-in functions that are no longer essential to learn, know
+or use in modern Python programming.  They have been kept here to maintain
+backwards compatibility with programs written for older versions of Python.
+
+Python programmers, trainers, students and bookwriters should feel free to
+bypass these functions without concerns about missing something important.
+
+
+.. function:: apply(function, args[, keywords])
+
+   The *function* argument must be a callable object (a user-defined or built-in
+   function or method, or a class object) and the *args* argument must be a
+   sequence.  The *function* is called with *args* as the argument list; the number
+   of arguments is the length of the tuple. If the optional *keywords* argument is
+   present, it must be a dictionary whose keys are strings.  It specifies keyword
+   arguments to be added to the end of the argument list. Calling :func:`apply` is
+   different from just calling ``function(args)``, since in that case there is
+   always exactly one argument.  The use of :func:`apply` is equivalent to
+   ``function(*args, **keywords)``. Use of :func:`apply` is not necessary since the
+   "extended call syntax," as used in the last example, is completely equivalent.
+
+   .. deprecated:: 2.3
+      Use the extended call syntax instead, as described above.
+
+
+.. function:: buffer(object[, offset[, size]])
+
+   The *object* argument must be an object that supports the buffer call interface
+   (such as strings, arrays, and buffers).  A new buffer object will be created
+   which references the *object* argument. The buffer object will be a slice from
+   the beginning of *object* (or from the specified *offset*). The slice will
+   extend to the end of *object* (or will have a length given by the *size*
+   argument).
+
+
+.. function:: coerce(x, y)
+
+   Return a tuple consisting of the two numeric arguments converted to a common
+   type, using the same rules as used by arithmetic operations. If coercion is not
+   possible, raise :exc:`TypeError`.
+
+
+.. function:: intern(string)
+
+   Enter *string* in the table of "interned" strings and return the interned string
+   -- which is *string* itself or a copy. Interning strings is useful to gain a
+   little performance on dictionary lookup -- if the keys in a dictionary are
+   interned, and the lookup key is interned, the key comparisons (after hashing)
+   can be done by a pointer compare instead of a string compare.  Normally, the
+   names used in Python programs are automatically interned, and the dictionaries
+   used to hold module, class or instance attributes have interned keys.
+
+   .. versionchanged:: 2.3
+      Interned strings are not immortal (like they used to be in Python 2.2 and
+      before); you must keep a reference to the return value of :func:`intern` around
+      to benefit from it.
+
+.. rubric:: Footnotes
+
+.. [#] It is used relatively rarely so does not warrant being made into a statement.
+
+.. [#] Specifying a buffer size currently has no effect on systems that don't have
+   :cfunc:`setvbuf`.  The interface to specify the buffer size is not done using a
+   method that calls :cfunc:`setvbuf`, because that may dump core when called after
+   any I/O has been performed, and there's no reliable way to determine whether
+   this is the case.
+
+.. [#] In the current implementation, local variable bindings cannot normally be
+   affected this way, but variables retrieved from other scopes (such as modules)
+   can be.  This may change.
+