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78 changes: 39 additions & 39 deletions Doc/library/datetime.rst
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Expand Up @@ -44,7 +44,7 @@ on efficient attribute extraction for output formatting and manipulation.

.. _datetime-naive-aware:

Aware and Naive Objects
Aware and naive objects
-----------------------

Date and time objects may be categorized as "aware" or "naive" depending on
Expand All @@ -65,7 +65,7 @@ understand and to work with, at the cost of ignoring some aspects of reality.

For applications requiring aware objects, :class:`.datetime` and :class:`.time`
objects have an optional time zone information attribute, :attr:`!tzinfo`, that
can be set to an instance of a subclass of the abstract :class:`tzinfo` class.
can be set to an instance of a subclass of the abstract :class:`!tzinfo` class.
These :class:`tzinfo` objects capture information about the offset from UTC
time, the time zone name, and whether daylight saving time is in effect.

Expand Down Expand Up @@ -99,7 +99,7 @@ The :mod:`!datetime` module exports the following constants:

.. versionadded:: 3.11

Available Types
Available types
---------------

.. class:: date
Expand Down Expand Up @@ -162,7 +162,7 @@ Subclass relationships::
date
datetime

Common Properties
Common properties
^^^^^^^^^^^^^^^^^

The :class:`date`, :class:`.datetime`, :class:`.time`, and :class:`timezone` types
Expand All @@ -173,7 +173,7 @@ share these common features:
dictionary keys.
- Objects of these types support efficient pickling via the :mod:`pickle` module.

Determining if an Object is Aware or Naive
Determining if an object is aware or naive
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Objects of the :class:`date` type are always naive.
Expand All @@ -199,7 +199,7 @@ objects.

.. _datetime-timedelta:

:class:`timedelta` Objects
:class:`timedelta` objects
--------------------------

A :class:`timedelta` object represents a duration, the difference between two
Expand Down Expand Up @@ -432,9 +432,9 @@ objects (see below).

.. versionchanged:: 3.2
Floor division and true division of a :class:`timedelta` object by another
:class:`timedelta` object are now supported, as are remainder operations and
:class:`!timedelta` object are now supported, as are remainder operations and
the :func:`divmod` function. True division and multiplication of a
:class:`timedelta` object by a :class:`float` object are now supported.
:class:`!timedelta` object by a :class:`float` object are now supported.

:class:`timedelta` objects support equality and order comparisons.

Expand Down Expand Up @@ -487,7 +487,7 @@ Examples of :class:`timedelta` arithmetic::

.. _datetime-date:

:class:`date` Objects
:class:`date` objects
---------------------

A :class:`date` object represents a date (year, month and day) in an idealized
Expand Down Expand Up @@ -700,7 +700,7 @@ Notes:
In other words, ``date1 < date2`` if and only if ``date1.toordinal() <
date2.toordinal()``.

Order comparison between a :class:`!date` object that is not also a
Order comparison between a :class:`date` object that is not also a
:class:`.datetime` instance and a :class:`!datetime` object raises
:exc:`TypeError`.

Expand Down Expand Up @@ -835,7 +835,7 @@ Instance methods:
literals <f-strings>` and when using :meth:`str.format`.
See also :ref:`strftime-strptime-behavior` and :meth:`date.isoformat`.

Examples of Usage: :class:`date`
Examples of usage: :class:`date`
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Example of counting days to an event::
Expand Down Expand Up @@ -905,15 +905,15 @@ More examples of working with :class:`date`:

.. _datetime-datetime:

:class:`.datetime` Objects
:class:`.datetime` objects
--------------------------

A :class:`.datetime` object is a single object containing all the information
from a :class:`date` object and a :class:`.time` object.

Like a :class:`date` object, :class:`.datetime` assumes the current Gregorian
calendar extended in both directions; like a :class:`.time` object,
:class:`.datetime` assumes there are exactly 3600\*24 seconds in every day.
:class:`!datetime` assumes there are exactly 3600\*24 seconds in every day.

Constructor:

Expand Down Expand Up @@ -1086,7 +1086,7 @@ Other constructors, all class methods:
are equal to the given :class:`.time` object's. If the *tzinfo*
argument is provided, its value is used to set the :attr:`.tzinfo` attribute
of the result, otherwise the :attr:`~.time.tzinfo` attribute of the *time* argument
is used. If the *date* argument is a :class:`.datetime` object, its time components
is used. If the *date* argument is a :class:`!datetime` object, its time components
and :attr:`.tzinfo` attributes are ignored.

For any :class:`.datetime` object ``d``,
Expand Down Expand Up @@ -1290,7 +1290,7 @@ Supported operations:
datetime, and no time zone adjustments are done even if the input is aware.

(3)
Subtraction of a :class:`.datetime` from a :class:`.datetime` is defined only if
Subtraction of a :class:`.datetime` from a :class:`!datetime` is defined only if
both operands are naive, or if both are aware. If one is aware and the other is
naive, :exc:`TypeError` is raised.

Expand All @@ -1308,15 +1308,15 @@ Supported operations:
:class:`.datetime` objects are equal if they represent the same date
and time, taking into account the time zone.

Naive and aware :class:`!datetime` objects are never equal.
Naive and aware :class:`.datetime` objects are never equal.

If both comparands are aware, and have the same :attr:`!tzinfo` attribute,
the :attr:`!tzinfo` and :attr:`~.datetime.fold` attributes are ignored and
the base datetimes are compared.
If both comparands are aware and have different :attr:`~.datetime.tzinfo`
attributes, the comparison acts as comparands were first converted to UTC
datetimes except that the implementation never overflows.
:class:`!datetime` instances in a repeated interval are never equal to
:class:`.datetime` instances in a repeated interval are never equal to
:class:`!datetime` instances in other time zone.

(5)
Expand Down Expand Up @@ -1513,7 +1513,7 @@ Instance methods:

Naive :class:`.datetime` instances are assumed to represent local
time and this method relies on platform C functions to perform
the conversion. Since :class:`.datetime` supports a wider range of
the conversion. Since :class:`!datetime` supports a wider range of
values than the platform C functions on many platforms, this
method may raise :exc:`OverflowError` or :exc:`OSError` for times
far in the past or far in the future.
Expand Down Expand Up @@ -1675,7 +1675,7 @@ Instance methods:
See also :ref:`strftime-strptime-behavior` and :meth:`datetime.isoformat`.


Examples of Usage: :class:`.datetime`
Examples of usage: :class:`.datetime`
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Examples of working with :class:`.datetime` objects:
Expand Down Expand Up @@ -1803,7 +1803,7 @@ Usage of ``KabulTz`` from above::

.. _datetime-time:

:class:`.time` Objects
:class:`.time` objects
----------------------

A :class:`.time` object represents a (local) time of day, independent of any particular
Expand Down Expand Up @@ -1974,7 +1974,7 @@ Instance methods:

Return a new :class:`.time` with the same values, but with specified
parameters updated. Note that ``tzinfo=None`` can be specified to create a
naive :class:`.time` from an aware :class:`.time`, without conversion of the
naive :class:`!time` from an aware :class:`!time`, without conversion of the
time data.

:class:`.time` objects are also supported by generic function
Expand Down Expand Up @@ -2072,7 +2072,7 @@ Instance methods:
``self.tzinfo.tzname(None)``, or raises an exception if the latter doesn't
return ``None`` or a string object.

Examples of Usage: :class:`.time`
Examples of usage: :class:`.time`
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Examples of working with a :class:`.time` object::
Expand Down Expand Up @@ -2105,7 +2105,7 @@ Examples of working with a :class:`.time` object::

.. _datetime-tzinfo:

:class:`tzinfo` Objects
:class:`tzinfo` objects
-----------------------

.. class:: tzinfo()
Expand All @@ -2116,14 +2116,14 @@ Examples of working with a :class:`.time` object::

An instance of (a concrete subclass of) :class:`tzinfo` can be passed to the
constructors for :class:`.datetime` and :class:`.time` objects. The latter objects
view their attributes as being in local time, and the :class:`tzinfo` object
view their attributes as being in local time, and the :class:`!tzinfo` object
supports methods revealing offset of local time from UTC, the name of the time
zone, and DST offset, all relative to a date or time object passed to them.

You need to derive a concrete subclass, and (at least)
supply implementations of the standard :class:`tzinfo` methods needed by the
:class:`.datetime` methods you use. The :mod:`!datetime` module provides
:class:`timezone`, a simple concrete subclass of :class:`tzinfo` which can
:class:`timezone`, a simple concrete subclass of :class:`!tzinfo` which can
represent time zones with fixed offset from UTC such as UTC itself or North
American EST and EDT.

Expand Down Expand Up @@ -2186,11 +2186,11 @@ Examples of working with a :class:`.time` object::
``tz.utcoffset(dt) - tz.dst(dt)``

must return the same result for every :class:`.datetime` *dt* with ``dt.tzinfo ==
tz``. For sane :class:`tzinfo` subclasses, this expression yields the time
tz``. For sane :class:`!tzinfo` subclasses, this expression yields the time
zone's "standard offset", which should not depend on the date or the time, but
only on geographic location. The implementation of :meth:`datetime.astimezone`
relies on this, but cannot detect violations; it's the programmer's
responsibility to ensure it. If a :class:`tzinfo` subclass cannot guarantee
responsibility to ensure it. If a :class:`!tzinfo` subclass cannot guarantee
this, it may be able to override the default implementation of
:meth:`tzinfo.fromutc` to work correctly with :meth:`~.datetime.astimezone` regardless.

Expand Down Expand Up @@ -2227,28 +2227,28 @@ Examples of working with a :class:`.time` object::
valid replies. Return ``None`` if a string name isn't known. Note that this is
a method rather than a fixed string primarily because some :class:`tzinfo`
subclasses will wish to return different names depending on the specific value
of *dt* passed, especially if the :class:`tzinfo` class is accounting for
of *dt* passed, especially if the :class:`!tzinfo` class is accounting for
daylight time.

The default implementation of :meth:`tzname` raises :exc:`NotImplementedError`.


These methods are called by a :class:`.datetime` or :class:`.time` object, in
response to their methods of the same names. A :class:`.datetime` object passes
itself as the argument, and a :class:`.time` object passes ``None`` as the
response to their methods of the same names. A :class:`!datetime` object passes
itself as the argument, and a :class:`!time` object passes ``None`` as the
argument. A :class:`tzinfo` subclass's methods should therefore be prepared to
accept a *dt* argument of ``None``, or of class :class:`.datetime`.
accept a *dt* argument of ``None``, or of class :class:`!datetime`.

When ``None`` is passed, it's up to the class designer to decide the best
response. For example, returning ``None`` is appropriate if the class wishes to
say that time objects don't participate in the :class:`tzinfo` protocols. It
may be more useful for ``utcoffset(None)`` to return the standard UTC offset, as
there is no other convention for discovering the standard offset.

When a :class:`.datetime` object is passed in response to a :class:`.datetime`
When a :class:`.datetime` object is passed in response to a :class:`!datetime`
method, ``dt.tzinfo`` is the same object as *self*. :class:`tzinfo` methods can
rely on this, unless user code calls :class:`tzinfo` methods directly. The
intent is that the :class:`tzinfo` methods interpret *dt* as being in local
rely on this, unless user code calls :class:`!tzinfo` methods directly. The
intent is that the :class:`!tzinfo` methods interpret *dt* as being in local
time, and not need worry about objects in other time zones.

There is one more :class:`tzinfo` method that a subclass may wish to override:
Expand Down Expand Up @@ -2358,7 +2358,7 @@ Note that the :class:`.datetime` instances that differ only by the value of the
Applications that can't bear wall-time ambiguities should explicitly check the
value of the :attr:`~.datetime.fold` attribute or avoid using hybrid
:class:`tzinfo` subclasses; there are no ambiguities when using :class:`timezone`,
or any other fixed-offset :class:`tzinfo` subclass (such as a class representing
or any other fixed-offset :class:`!tzinfo` subclass (such as a class representing
only EST (fixed offset -5 hours), or only EDT (fixed offset -4 hours)).

.. seealso::
Expand All @@ -2381,7 +2381,7 @@ only EST (fixed offset -5 hours), or only EDT (fixed offset -4 hours)).

.. _datetime-timezone:

:class:`timezone` Objects
:class:`timezone` objects
-------------------------

The :class:`timezone` class is a subclass of :class:`tzinfo`, each
Expand Down Expand Up @@ -2457,7 +2457,7 @@ Class attributes:

.. _strftime-strptime-behavior:

:meth:`~.datetime.strftime` and :meth:`~.datetime.strptime` Behavior
:meth:`~.datetime.strftime` and :meth:`~.datetime.strptime` behavior
--------------------------------------------------------------------

:class:`date`, :class:`.datetime`, and :class:`.time` objects all support a
Expand All @@ -2484,7 +2484,7 @@ versus :meth:`~.datetime.strptime`:

.. _format-codes:

:meth:`~.datetime.strftime` and :meth:`~.datetime.strptime` Format Codes
:meth:`~.datetime.strftime` and :meth:`~.datetime.strptime` Format codes
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

These methods accept format codes that can be used to parse and format dates::
Expand Down Expand Up @@ -2644,7 +2644,7 @@ differences between platforms in handling of unsupported format specifiers.
.. versionadded:: 3.15
``%:z`` was added for :meth:`~.datetime.strptime`

Technical Detail
Technical detail
^^^^^^^^^^^^^^^^

Broadly speaking, ``d.strftime(fmt)`` acts like the :mod:`time` module's
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