bpo-38738: Fix formatting of True and False. (GH-17083)

* "Return true/false" is replaced with "Return ``True``/``False``"
  if the function actually returns a bool.
* Fixed formatting of some True and False literals (now in monospace).
* Replaced "True/False" with "true/false" if it can be not only bool.
* Replaced some 1/0 with True/False if it corresponds the code.
* "Returns <bool>" is replaced with "Return <bool>".

Author: serhiy-storchaka

Doc/library/asyncio-stream.rst

@@ -263,8 +263,8 @@ StreamWriter
 
    .. method:: can_write_eof()
 
-      Return *True* if the underlying transport supports
-      the :meth:`write_eof` method, *False* otherwise.
+      Return ``True`` if the underlying transport supports
+      the :meth:`write_eof` method, ``False`` otherwise.
 
    .. method:: write_eof()
 

Doc/library/dataclasses.rst

@@ -153,7 +153,7 @@ Module-level decorators, classes, and functions
      method of the superclass will be used (if the superclass is
      :class:`object`, this means it will fall back to id-based hashing).
 
-   - ``frozen``: If true (the default is False), assigning to fields will
+   - ``frozen``: If true (the default is ``False``), assigning to fields will
      generate an exception.  This emulates read-only frozen instances.  If
      :meth:`__setattr__` or :meth:`__delattr__` is defined in the class, then
      :exc:`TypeError` is raised.  See the discussion below.
@@ -386,8 +386,8 @@ Module-level decorators, classes, and functions
 
 .. function:: is_dataclass(class_or_instance)
 
-   Returns True if its parameter is a dataclass or an instance of one,
-   otherwise returns False.
+   Return ``True`` if its parameter is a dataclass or an instance of one,
+   otherwise return ``False``.
 
    If you need to know if a class is an instance of a dataclass (and
    not a dataclass itself), then add a further check for ``not

Doc/library/dialog.rst

@@ -73,7 +73,7 @@ listed below:
 
  | *defaultextension* - default extension to append to file (save dialogs)
 
- | *multiple* - when True, selection of multiple items is allowed
+ | *multiple* - when true, selection of multiple items is allowed
 
 
 **Static factory functions**
@@ -227,4 +227,4 @@ is the base class for dialogs defined in other supporting modules.
 
 .. seealso::
 
-   Modules :mod:`tkinter.messagebox`, :ref:`tut-files`
+   Modules :mod:`tkinter.messagebox`, :ref:`tut-files`

Doc/library/difflib.rst

@@ -338,14 +338,14 @@ diffs. For comparing directories and files, see also, the :mod:`filecmp` module.
 
 .. function:: IS_LINE_JUNK(line)
 
-   Return true for ignorable lines.  The line *line* is ignorable if *line* is
+   Return ``True`` for ignorable lines.  The line *line* is ignorable if *line* is
    blank or contains a single ``'#'``, otherwise it is not ignorable.  Used as a
    default for parameter *linejunk* in :func:`ndiff` in older versions.
 
 
 .. function:: IS_CHARACTER_JUNK(ch)
 
-   Return true for ignorable characters.  The character *ch* is ignorable if *ch*
+   Return ``True`` for ignorable characters.  The character *ch* is ignorable if *ch*
    is a space or tab, otherwise it is not ignorable.  Used as a default for
    parameter *charjunk* in :func:`ndiff`.
 
@@ -370,7 +370,7 @@ The :class:`SequenceMatcher` class has this constructor:
    Optional argument *isjunk* must be ``None`` (the default) or a one-argument
    function that takes a sequence element and returns true if and only if the
    element is "junk" and should be ignored. Passing ``None`` for *isjunk* is
-   equivalent to passing ``lambda x: 0``; in other words, no elements are ignored.
+   equivalent to passing ``lambda x: False``; in other words, no elements are ignored.
    For example, pass::
 
       lambda x: x in " \t"

Doc/library/doctest.rst

@@ -1529,7 +1529,7 @@ OutputChecker objects
 
    A class used to check the whether the actual output from a doctest example
    matches the expected output.  :class:`OutputChecker` defines two methods:
-   :meth:`check_output`, which compares a given pair of outputs, and returns true
+   :meth:`check_output`, which compares a given pair of outputs, and returns ``True``
    if they match; and :meth:`output_difference`, which returns a string describing
    the differences between two outputs.
 

Doc/library/email.compat32-message.rst

@@ -308,7 +308,7 @@ Here are the methods of the :class:`Message` class:
 
    .. method:: __contains__(name)
 
-      Return true if the message object has a field named *name*. Matching is
+      Return ``True`` if the message object has a field named *name*. Matching is
       done case-insensitively and *name* should not include the trailing colon.
       Used for the ``in`` operator, e.g.::
 

Doc/library/email.errors.rst

@@ -99,7 +99,7 @@ All defect classes are subclassed from :class:`email.errors.MessageDefect`.
 * :class:`MultipartInvariantViolationDefect` -- A message claimed to be a
   :mimetype:`multipart`, but no subparts were found.  Note that when a message
   has this defect, its :meth:`~email.message.Message.is_multipart` method may
-  return false even though its content type claims to be :mimetype:`multipart`.
+  return ``False`` even though its content type claims to be :mimetype:`multipart`.
 
 * :class:`InvalidBase64PaddingDefect` -- When decoding a block of base64
   encoded bytes, the padding was not correct.  Enough padding is added to

Doc/library/email.message.rst

@@ -178,7 +178,7 @@ message objects.
 
    .. method:: __contains__(name)
 
-      Return true if the message object has a field named *name*. Matching is
+      Return ``True`` if the message object has a field named *name*. Matching is
       done without regard to case and *name* does not include the trailing
       colon.  Used for the ``in`` operator.  For example::
 

Doc/library/fileinput.rst

@@ -109,14 +109,14 @@ if there is no active state, :exc:`RuntimeError` is raised.
 
 .. function:: isfirstline()
 
-   Returns true if the line just read is the first line of its file, otherwise
-   returns false.
+   Return ``True`` if the line just read is the first line of its file, otherwise
+   return ``False``.
 
 
 .. function:: isstdin()
 
-   Returns true if the last line was read from ``sys.stdin``, otherwise returns
-   false.
+   Return ``True`` if the last line was read from ``sys.stdin``, otherwise return
+   ``False``.
 
 
 .. function:: nextfile()

Doc/library/functions.rst

@@ -181,8 +181,8 @@ are always available.  They are listed here in alphabetical order.
 .. 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.
+   :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);
    instances are callable if their class has a :meth:`__call__` method.
 
@@ -840,19 +840,19 @@ are always available.  They are listed here in alphabetical order.
 
 .. function:: isinstance(object, classinfo)
 
-   Return true if the *object* argument is an instance of the *classinfo*
+   Return ``True`` if the *object* argument is an instance of the *classinfo*
    argument, or of a (direct, indirect or :term:`virtual <abstract base
    class>`) subclass thereof.  If *object* is not
-   an object of the given type, the function always returns false.
+   an object of the given type, the function always returns ``False``.
    If *classinfo* is a tuple of type objects (or recursively, other such
-   tuples), return true if *object* is an instance of any of the types.
+   tuples), return ``True`` if *object* is an instance of any of the types.
    If *classinfo* is not a type or tuple of types and such tuples,
    a :exc:`TypeError` exception is raised.
 
 
 .. function:: issubclass(class, classinfo)
 
-   Return true if *class* is a subclass (direct, indirect or :term:`virtual
+   Return ``True`` if *class* is a subclass (direct, indirect or :term:`virtual
    <abstract base class>`) 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

Doc/library/gc.rst

@@ -35,7 +35,7 @@ The :mod:`gc` module provides the following functions:
 
 .. function:: isenabled()
 
-   Returns true if automatic collection is enabled.
+   Return ``True`` if automatic collection is enabled.
 
 
 .. function:: collect(generation=2)

Doc/library/hashlib.rst

@@ -82,8 +82,8 @@ library that Python uses on your platform. On most platforms the
 
 .. versionchanged:: 3.9
    All hashlib constructors take a keyword-only argument *usedforsecurity*
-   with default value *True*. A false value allows the use of insecure and
-   blocked hashing algorithms in restricted environments. *False* indicates
+   with default value ``True``. A false value allows the use of insecure and
+   blocked hashing algorithms in restricted environments. ``False`` indicates
    that the hashing algorithm is not used in a security context, e.g. as a
    non-cryptographic one-way compression function.
 

Doc/library/http.cookiejar.rst

@@ -378,7 +378,7 @@ methods:
 
 .. method:: CookiePolicy.domain_return_ok(domain, request)
 
-   Return false if cookies should not be returned, given cookie domain.
+   Return ``False`` if cookies should not be returned, given cookie domain.
 
    This method is an optimization.  It removes the need for checking every cookie
    with a particular domain (which might involve reading many files).  Returning
@@ -402,7 +402,7 @@ methods:
 
 .. method:: CookiePolicy.path_return_ok(path, request)
 
-   Return false if cookies should not be returned, given cookie path.
+   Return ``False`` if cookies should not be returned, given cookie path.
 
    See the documentation for :meth:`domain_return_ok`.
 
@@ -711,7 +711,7 @@ accessed using the following methods:
 
 .. method:: Cookie.has_nonstandard_attr(name)
 
-   Return true if cookie has the named cookie-attribute.
+   Return ``True`` if cookie has the named cookie-attribute.
 
 
 .. method:: Cookie.get_nonstandard_attr(name, default=None)

Doc/library/importlib.rst

@@ -1168,7 +1168,7 @@ find and load modules.
 
    .. method:: is_package(fullname)
 
-      Return true if :attr:`path` appears to be for a package.
+      Return ``True`` if :attr:`path` appears to be for a package.
 
    .. method:: path_stats(path)
 

Doc/library/inspect.rst

@@ -277,63 +277,63 @@ attributes:
 
 .. function:: ismodule(object)
 
-   Return true if the object is a module.
+   Return ``True`` if the object is a module.
 
 
 .. function:: isclass(object)
 
-   Return true if the object is a class, whether built-in or created in Python
+   Return ``True`` if the object is a class, whether built-in or created in Python
    code.
 
 
 .. function:: ismethod(object)
 
-   Return true if the object is a bound method written in Python.
+   Return ``True`` if the object is a bound method written in Python.
 
 
 .. function:: isfunction(object)
 
-   Return true if the object is a Python function, which includes functions
+   Return ``True`` if the object is a Python function, which includes functions
    created by a :term:`lambda` expression.
 
 
 .. function:: isgeneratorfunction(object)
 
-   Return true if the object is a Python generator function.
+   Return ``True`` if the object is a Python generator function.
 
    .. versionchanged:: 3.8
-      Functions wrapped in :func:`functools.partial` now return true if the
+      Functions wrapped in :func:`functools.partial` now return ``True`` if the
       wrapped function is a Python generator function.
 
 
 .. function:: isgenerator(object)
 
-   Return true if the object is a generator.
+   Return ``True`` if the object is a generator.
 
 
 .. function:: iscoroutinefunction(object)
 
-   Return true if the object is a :term:`coroutine function`
+   Return ``True`` if the object is a :term:`coroutine function`
    (a function defined with an :keyword:`async def` syntax).
 
    .. versionadded:: 3.5
 
    .. versionchanged:: 3.8
-      Functions wrapped in :func:`functools.partial` now return true if the
+      Functions wrapped in :func:`functools.partial` now return ``True`` if the
       wrapped function is a :term:`coroutine function`.
 
 
 .. function:: iscoroutine(object)
 
-   Return true if the object is a :term:`coroutine` created by an
+   Return ``True`` if the object is a :term:`coroutine` created by an
    :keyword:`async def` function.
 
    .. versionadded:: 3.5
 
 
 .. function:: isawaitable(object)
 
-   Return true if the object can be used in :keyword:`await` expression.
+   Return ``True`` if the object can be used in :keyword:`await` expression.
 
    Can also be used to distinguish generator-based coroutines from regular
    generators::
@@ -352,7 +352,7 @@ attributes:
 
 .. function:: isasyncgenfunction(object)
 
-   Return true if the object is an :term:`asynchronous generator` function,
+   Return ``True`` if the object is an :term:`asynchronous generator` function,
    for example::
 
     >>> async def agen():
@@ -364,50 +364,50 @@ attributes:
    .. versionadded:: 3.6
 
    .. versionchanged:: 3.8
-      Functions wrapped in :func:`functools.partial` now return true if the
+      Functions wrapped in :func:`functools.partial` now return ``True`` if the
       wrapped function is a :term:`asynchronous generator` function.
 
 
 .. function:: isasyncgen(object)
 
-   Return true if the object is an :term:`asynchronous generator iterator`
+   Return ``True`` if the object is an :term:`asynchronous generator iterator`
    created by an :term:`asynchronous generator` function.
 
    .. versionadded:: 3.6
 
 .. function:: istraceback(object)
 
-   Return true if the object is a traceback.
+   Return ``True`` if the object is a traceback.
 
 
 .. function:: isframe(object)
 
-   Return true if the object is a frame.
+   Return ``True`` if the object is a frame.
 
 
 .. function:: iscode(object)
 
-   Return true if the object is a code.
+   Return ``True`` if the object is a code.
 
 
 .. function:: isbuiltin(object)
 
-   Return true if the object is a built-in function or a bound built-in method.
+   Return ``True`` if the object is a built-in function or a bound built-in method.
 
 
 .. function:: isroutine(object)
 
-   Return true if the object is a user-defined or built-in function or method.
+   Return ``True`` if the object is a user-defined or built-in function or method.
 
 
 .. function:: isabstract(object)
 
-   Return true if the object is an abstract base class.
+   Return ``True`` if the object is an abstract base class.
 
 
 .. function:: ismethoddescriptor(object)
 
-   Return true if the object is a method descriptor, but not if
+   Return ``True`` if the object is a method descriptor, but not if
    :func:`ismethod`, :func:`isclass`, :func:`isfunction` or :func:`isbuiltin`
    are true.
 
@@ -418,14 +418,14 @@ attributes:
    sensible, and :attr:`__doc__` often is.
 
    Methods implemented via descriptors that also pass one of the other tests
-   return false from the :func:`ismethoddescriptor` test, simply because the
+   return ``False`` from the :func:`ismethoddescriptor` test, simply because the
    other tests promise more -- you can, e.g., count on having the
    :attr:`__func__` attribute (etc) when an object passes :func:`ismethod`.
 
 
 .. function:: isdatadescriptor(object)
 
-   Return true if the object is a data descriptor.
+   Return ``True`` if the object is a data descriptor.
 
    Data descriptors have both a :attr:`~object.__get__` and a :attr:`~object.__set__` method.
    Examples are properties (defined in Python), getsets, and members.  The
@@ -438,7 +438,7 @@ attributes:
 
 .. function:: isgetsetdescriptor(object)
 
-   Return true if the object is a getset descriptor.
+   Return ``True`` if the object is a getset descriptor.
 
    .. impl-detail::
 
@@ -449,7 +449,7 @@ attributes:
 
 .. function:: ismemberdescriptor(object)
 
-   Return true if the object is a member descriptor.
+   Return ``True`` if the object is a member descriptor.
 
    .. impl-detail::