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:mod:`datetime` --- Basic date and time types
=============================================
.. module:: datetime
:synopsis: Basic date and time types.
.. moduleauthor:: Tim Peters <tim@zope.com>
.. sectionauthor:: Tim Peters <tim@zope.com>
.. sectionauthor:: A.M. Kuchling <amk@amk.ca>
**Source code:** :source:`Lib/datetime.py`
--------------
.. XXX what order should the types be discussed in?
The :mod:`datetime` module supplies classes for manipulating dates and times.
While date and time arithmetic is supported, the focus of the implementation is
on efficient attribute extraction for output formatting and manipulation.
.. tip::
Skip to :ref:`the format codes <format-codes>`.
.. seealso::
Module :mod:`calendar`
General calendar related functions.
Module :mod:`time`
Time access and conversions.
Module :mod:`zoneinfo`
Concrete time zones representing the IANA time zone database.
Package `dateutil <https://dateutil.readthedocs.io/en/stable/>`_
Third-party library with expanded time zone and parsing support.
Package `DateType <https://pypi.org/project/datetype/>`_
Third-party library that introduces distinct static types to e.g. allow
:term:`static type checkers <static type checker>`
to differentiate between naive and aware datetimes.
.. _datetime-naive-aware:
Aware and Naive Objects
-----------------------
Date and time objects may be categorized as "aware" or "naive" depending on
whether or not they include timezone information.
With sufficient knowledge of applicable algorithmic and political time
adjustments, such as time zone and daylight saving time information,
an **aware** object can locate itself relative to other aware objects.
An aware object represents a specific moment in time that is not open to
interpretation. [#]_
A **naive** object does not contain enough information to unambiguously locate
itself relative to other date/time objects. Whether a naive object represents
Coordinated Universal Time (UTC), local time, or time in some other timezone is
purely up to the program, just like it is up to the program whether a
particular number represents metres, miles, or mass. Naive objects are easy to
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.
These :class:`tzinfo` objects capture information about the offset from UTC
time, the time zone name, and whether daylight saving time is in effect.
Only one concrete :class:`tzinfo` class, the :class:`timezone` class, is
supplied by the :mod:`datetime` module. The :class:`timezone` class can
represent simple timezones with fixed offsets from UTC, such as UTC itself or
North American EST and EDT timezones. Supporting timezones at deeper levels of
detail is up to the application. The rules for time adjustment across the
world are more political than rational, change frequently, and there is no
standard suitable for every application aside from UTC.
Constants
---------
The :mod:`datetime` module exports the following constants:
.. data:: MINYEAR
The smallest year number allowed in a :class:`date` or :class:`.datetime` object.
:const:`MINYEAR` is ``1``.
.. data:: MAXYEAR
The largest year number allowed in a :class:`date` or :class:`.datetime` object.
:const:`MAXYEAR` is ``9999``.
.. attribute:: UTC
Alias for the UTC timezone singleton :attr:`datetime.timezone.utc`.
.. versionadded:: 3.11
Available Types
---------------
.. class:: date
:noindex:
An idealized naive date, assuming the current Gregorian calendar always was, and
always will be, in effect. Attributes: :attr:`year`, :attr:`month`, and
:attr:`day`.
.. class:: time
:noindex:
An idealized time, independent of any particular day, assuming that every day
has exactly 24\*60\*60 seconds. (There is no notion of "leap seconds" here.)
Attributes: :attr:`hour`, :attr:`minute`, :attr:`second`, :attr:`microsecond`,
and :attr:`.tzinfo`.
.. class:: datetime
:noindex:
A combination of a date and a time. Attributes: :attr:`year`, :attr:`month`,
:attr:`day`, :attr:`hour`, :attr:`minute`, :attr:`second`, :attr:`microsecond`,
and :attr:`.tzinfo`.
.. class:: timedelta
:noindex:
A duration expressing the difference between two :class:`date`, :class:`.time`,
or :class:`.datetime` instances to microsecond resolution.
.. class:: tzinfo
:noindex:
An abstract base class for time zone information objects. These are used by the
:class:`.datetime` and :class:`.time` classes to provide a customizable notion of
time adjustment (for example, to account for time zone and/or daylight saving
time).
.. class:: timezone
:noindex:
A class that implements the :class:`tzinfo` abstract base class as a
fixed offset from the UTC.
.. versionadded:: 3.2
Objects of these types are immutable.
Subclass relationships::
object
timedelta
tzinfo
timezone
time
date
datetime
Common Properties
^^^^^^^^^^^^^^^^^
The :class:`date`, :class:`.datetime`, :class:`.time`, and :class:`timezone` types
share these common features:
- Objects of these types are immutable.
- Objects of these types are :term:`hashable`, meaning that they can be used as
dictionary keys.
- Objects of these types support efficient pickling via the :mod:`pickle` module.
Determining if an Object is Aware or Naive
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Objects of the :class:`date` type are always naive.
An object of type :class:`.time` or :class:`.datetime` may be aware or naive.
A :class:`.datetime` object *d* is aware if both of the following hold:
1. ``d.tzinfo`` is not ``None``
2. ``d.tzinfo.utcoffset(d)`` does not return ``None``
Otherwise, *d* is naive.
A :class:`.time` object *t* is aware if both of the following hold:
1. ``t.tzinfo`` is not ``None``
2. ``t.tzinfo.utcoffset(None)`` does not return ``None``.
Otherwise, *t* is naive.
The distinction between aware and naive doesn't apply to :class:`timedelta`
objects.
.. _datetime-timedelta:
:class:`timedelta` Objects
--------------------------
A :class:`timedelta` object represents a duration, the difference between two
dates or times.
.. class:: timedelta(days=0, seconds=0, microseconds=0, milliseconds=0, minutes=0, hours=0, weeks=0)
All arguments are optional and default to ``0``. Arguments may be integers
or floats, and may be positive or negative.
Only *days*, *seconds* and *microseconds* are stored internally.
Arguments are converted to those units:
* A millisecond is converted to 1000 microseconds.
* A minute is converted to 60 seconds.
* An hour is converted to 3600 seconds.
* A week is converted to 7 days.
and days, seconds and microseconds are then normalized so that the
representation is unique, with
* ``0 <= microseconds < 1000000``
* ``0 <= seconds < 3600*24`` (the number of seconds in one day)
* ``-999999999 <= days <= 999999999``
The following example illustrates how any arguments besides
*days*, *seconds* and *microseconds* are "merged" and normalized into those
three resulting attributes::
>>> from datetime import timedelta
>>> delta = timedelta(
... days=50,
... seconds=27,
... microseconds=10,
... milliseconds=29000,
... minutes=5,
... hours=8,
... weeks=2
... )
>>> # Only days, seconds, and microseconds remain
>>> delta
datetime.timedelta(days=64, seconds=29156, microseconds=10)
If any argument is a float and there are fractional microseconds,
the fractional microseconds left over from all arguments are
combined and their sum is rounded to the nearest microsecond using
round-half-to-even tiebreaker. If no argument is a float, the
conversion and normalization processes are exact (no information is
lost).
If the normalized value of days lies outside the indicated range,
:exc:`OverflowError` is raised.
Note that normalization of negative values may be surprising at first. For
example::
>>> from datetime import timedelta
>>> d = timedelta(microseconds=-1)
>>> (d.days, d.seconds, d.microseconds)
(-1, 86399, 999999)
Class attributes:
.. attribute:: timedelta.min
The most negative :class:`timedelta` object, ``timedelta(-999999999)``.
.. attribute:: timedelta.max
The most positive :class:`timedelta` object, ``timedelta(days=999999999,
hours=23, minutes=59, seconds=59, microseconds=999999)``.
.. attribute:: timedelta.resolution
The smallest possible difference between non-equal :class:`timedelta` objects,
``timedelta(microseconds=1)``.
Note that, because of normalization, ``timedelta.max`` > ``-timedelta.min``.
``-timedelta.max`` is not representable as a :class:`timedelta` object.
Instance attributes (read-only):
+------------------+--------------------------------------------+
| Attribute | Value |
+==================+============================================+
| ``days`` | Between -999999999 and 999999999 inclusive |
+------------------+--------------------------------------------+
| ``seconds`` | Between 0 and 86399 inclusive |
+------------------+--------------------------------------------+
| ``microseconds`` | Between 0 and 999999 inclusive |
+------------------+--------------------------------------------+
Supported operations:
.. XXX this table is too wide!
+--------------------------------+-----------------------------------------------+
| Operation | Result |
+================================+===============================================+
| ``t1 = t2 + t3`` | Sum of *t2* and *t3*. Afterwards *t1*-*t2* == |
| | *t3* and *t1*-*t3* == *t2* are true. (1) |
+--------------------------------+-----------------------------------------------+
| ``t1 = t2 - t3`` | Difference of *t2* and *t3*. Afterwards *t1* |
| | == *t2* - *t3* and *t2* == *t1* + *t3* are |
| | true. (1)(6) |
+--------------------------------+-----------------------------------------------+
| ``t1 = t2 * i or t1 = i * t2`` | Delta multiplied by an integer. |
| | Afterwards *t1* // i == *t2* is true, |
| | provided ``i != 0``. |
+--------------------------------+-----------------------------------------------+
| | In general, *t1* \* i == *t1* \* (i-1) + *t1* |
| | is true. (1) |
+--------------------------------+-----------------------------------------------+
| ``t1 = t2 * f or t1 = f * t2`` | Delta multiplied by a float. The result is |
| | rounded to the nearest multiple of |
| | timedelta.resolution using round-half-to-even.|
+--------------------------------+-----------------------------------------------+
| ``f = t2 / t3`` | Division (3) of overall duration *t2* by |
| | interval unit *t3*. Returns a :class:`float` |
| | object. |
+--------------------------------+-----------------------------------------------+
| ``t1 = t2 / f or t1 = t2 / i`` | Delta divided by a float or an int. The result|
| | is rounded to the nearest multiple of |
| | timedelta.resolution using round-half-to-even.|
+--------------------------------+-----------------------------------------------+
| ``t1 = t2 // i`` or | The floor is computed and the remainder (if |
| ``t1 = t2 // t3`` | any) is thrown away. In the second case, an |
| | integer is returned. (3) |
+--------------------------------+-----------------------------------------------+
| ``t1 = t2 % t3`` | The remainder is computed as a |
| | :class:`timedelta` object. (3) |
+--------------------------------+-----------------------------------------------+
| ``q, r = divmod(t1, t2)`` | Computes the quotient and the remainder: |
| | ``q = t1 // t2`` (3) and ``r = t1 % t2``. |
| | q is an integer and r is a :class:`timedelta` |
| | object. |
+--------------------------------+-----------------------------------------------+
| ``+t1`` | Returns a :class:`timedelta` object with the |
| | same value. (2) |
+--------------------------------+-----------------------------------------------+
| ``-t1`` | equivalent to |
| | :class:`timedelta`\ (-*t1.days*, |
| | -*t1.seconds*, -*t1.microseconds*), |
| | and to *t1*\* -1. (1)(4) |
+--------------------------------+-----------------------------------------------+
| ``abs(t)`` | equivalent to +\ *t* when ``t.days >= 0``, |
| | and to -*t* when ``t.days < 0``. (2) |
+--------------------------------+-----------------------------------------------+
| ``str(t)`` | Returns a string in the form |
| | ``[D day[s], ][H]H:MM:SS[.UUUUUU]``, where D |
| | is negative for negative ``t``. (5) |
+--------------------------------+-----------------------------------------------+
| ``repr(t)`` | Returns a string representation of the |
| | :class:`timedelta` object as a constructor |
| | call with canonical attribute values. |
+--------------------------------+-----------------------------------------------+
Notes:
(1)
This is exact but may overflow.
(2)
This is exact and cannot overflow.
(3)
Division by 0 raises :exc:`ZeroDivisionError`.
(4)
-*timedelta.max* is not representable as a :class:`timedelta` object.
(5)
String representations of :class:`timedelta` objects are normalized
similarly to their internal representation. This leads to somewhat
unusual results for negative timedeltas. For example::
>>> timedelta(hours=-5)
datetime.timedelta(days=-1, seconds=68400)
>>> print(_)
-1 day, 19:00:00
(6)
The expression ``t2 - t3`` will always be equal to the expression ``t2 + (-t3)`` except
when t3 is equal to ``timedelta.max``; in that case the former will produce a result
while the latter will overflow.
In addition to the operations listed above, :class:`timedelta` objects support
certain additions and subtractions with :class:`date` and :class:`.datetime`
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
the :func:`divmod` function. True division and multiplication of a
:class:`timedelta` object by a :class:`float` object are now supported.
Comparisons of :class:`timedelta` objects are supported, with some caveats.
The comparisons ``==`` or ``!=`` *always* return a :class:`bool`, no matter
the type of the compared object::
>>> from datetime import timedelta
>>> delta1 = timedelta(seconds=57)
>>> delta2 = timedelta(hours=25, seconds=2)
>>> delta2 != delta1
True
>>> delta2 == 5
False
For all other comparisons (such as ``<`` and ``>``), when a :class:`timedelta`
object is compared to an object of a different type, :exc:`TypeError`
is raised::
>>> delta2 > delta1
True
>>> delta2 > 5
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: '>' not supported between instances of 'datetime.timedelta' and 'int'
In Boolean contexts, a :class:`timedelta` object is
considered to be true if and only if it isn't equal to ``timedelta(0)``.
Instance methods:
.. method:: timedelta.total_seconds()
Return the total number of seconds contained in the duration. Equivalent to
``td / timedelta(seconds=1)``. For interval units other than seconds, use the
division form directly (e.g. ``td / timedelta(microseconds=1)``).
Note that for very large time intervals (greater than 270 years on
most platforms) this method will lose microsecond accuracy.
.. versionadded:: 3.2
Examples of usage: :class:`timedelta`
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
An additional example of normalization::
>>> # Components of another_year add up to exactly 365 days
>>> from datetime import timedelta
>>> year = timedelta(days=365)
>>> another_year = timedelta(weeks=40, days=84, hours=23,
... minutes=50, seconds=600)
>>> year == another_year
True
>>> year.total_seconds()
31536000.0
Examples of :class:`timedelta` arithmetic::
>>> from datetime import timedelta
>>> year = timedelta(days=365)
>>> ten_years = 10 * year
>>> ten_years
datetime.timedelta(days=3650)
>>> ten_years.days // 365
10
>>> nine_years = ten_years - year
>>> nine_years
datetime.timedelta(days=3285)
>>> three_years = nine_years // 3
>>> three_years, three_years.days // 365
(datetime.timedelta(days=1095), 3)
.. _datetime-date:
:class:`date` Objects
---------------------
A :class:`date` object represents a date (year, month and day) in an idealized
calendar, the current Gregorian calendar indefinitely extended in both
directions.
January 1 of year 1 is called day number 1, January 2 of year 1 is
called day number 2, and so on. [#]_
.. class:: date(year, month, day)
All arguments are required. Arguments must be integers, in the following
ranges:
* ``MINYEAR <= year <= MAXYEAR``
* ``1 <= month <= 12``
* ``1 <= day <= number of days in the given month and year``
If an argument outside those ranges is given, :exc:`ValueError` is raised.
Other constructors, all class methods:
.. classmethod:: date.today()
Return the current local date.
This is equivalent to ``date.fromtimestamp(time.time())``.
.. classmethod:: date.fromtimestamp(timestamp)
Return the local date corresponding to the POSIX timestamp, such as is
returned by :func:`time.time`.
This may raise :exc:`OverflowError`, if the timestamp is out
of the range of values supported by the platform C :c:func:`localtime`
function, and :exc:`OSError` on :c:func:`localtime` failure.
It's common for this to be restricted to years from 1970 through 2038. Note
that on non-POSIX systems that include leap seconds in their notion of a
timestamp, leap seconds are ignored by :meth:`fromtimestamp`.
.. versionchanged:: 3.3
Raise :exc:`OverflowError` instead of :exc:`ValueError` if the timestamp
is out of the range of values supported by the platform C
:c:func:`localtime` function. Raise :exc:`OSError` instead of
:exc:`ValueError` on :c:func:`localtime` failure.
.. classmethod:: date.fromordinal(ordinal)
Return the date corresponding to the proleptic Gregorian ordinal, where
January 1 of year 1 has ordinal 1.
:exc:`ValueError` is raised unless ``1 <= ordinal <=
date.max.toordinal()``. For any date *d*,
``date.fromordinal(d.toordinal()) == d``.
.. classmethod:: date.fromisoformat(date_string)
Return a :class:`date` corresponding to a *date_string* given in any valid
ISO 8601 format, except ordinal dates (e.g. ``YYYY-DDD``)::
>>> from datetime import date
>>> date.fromisoformat('2019-12-04')
datetime.date(2019, 12, 4)
>>> date.fromisoformat('20191204')
datetime.date(2019, 12, 4)
>>> date.fromisoformat('2021-W01-1')
datetime.date(2021, 1, 4)
.. versionadded:: 3.7
.. versionchanged:: 3.11
Previously, this method only supported the format ``YYYY-MM-DD``.
.. classmethod:: date.fromisocalendar(year, week, day)
Return a :class:`date` corresponding to the ISO calendar date specified by
year, week and day. This is the inverse of the function :meth:`date.isocalendar`.
.. versionadded:: 3.8
Class attributes:
.. attribute:: date.min
The earliest representable date, ``date(MINYEAR, 1, 1)``.
.. attribute:: date.max
The latest representable date, ``date(MAXYEAR, 12, 31)``.
.. attribute:: date.resolution
The smallest possible difference between non-equal date objects,
``timedelta(days=1)``.
Instance attributes (read-only):
.. attribute:: date.year
Between :const:`MINYEAR` and :const:`MAXYEAR` inclusive.
.. attribute:: date.month
Between 1 and 12 inclusive.
.. attribute:: date.day
Between 1 and the number of days in the given month of the given year.
Supported operations:
+-------------------------------+----------------------------------------------+
| Operation | Result |
+===============================+==============================================+
| ``date2 = date1 + timedelta`` | *date2* will be ``timedelta.days`` days |
| | after *date1*. (1) |
+-------------------------------+----------------------------------------------+
| ``date2 = date1 - timedelta`` | Computes *date2* such that ``date2 + |
| | timedelta == date1``. (2) |
+-------------------------------+----------------------------------------------+
| ``timedelta = date1 - date2`` | \(3) |
+-------------------------------+----------------------------------------------+
| ``date1 < date2`` | *date1* is considered less than *date2* when |
| | *date1* precedes *date2* in time. (4) |
+-------------------------------+----------------------------------------------+
Notes:
(1)
*date2* is moved forward in time if ``timedelta.days > 0``, or backward if
``timedelta.days < 0``. Afterward ``date2 - date1 == timedelta.days``.
``timedelta.seconds`` and ``timedelta.microseconds`` are ignored.
:exc:`OverflowError` is raised if ``date2.year`` would be smaller than
:const:`MINYEAR` or larger than :const:`MAXYEAR`.
(2)
``timedelta.seconds`` and ``timedelta.microseconds`` are ignored.
(3)
This is exact, and cannot overflow. timedelta.seconds and
timedelta.microseconds are 0, and date2 + timedelta == date1 after.
(4)
In other words, ``date1 < date2`` if and only if ``date1.toordinal() <
date2.toordinal()``. Date comparison raises :exc:`TypeError` if
the other comparand isn't also a :class:`date` object. However,
``NotImplemented`` is returned instead if the other comparand has a
:meth:`timetuple` attribute. This hook gives other kinds of date objects a
chance at implementing mixed-type comparison. If not, when a :class:`date`
object is compared to an object of a different type, :exc:`TypeError` is raised
unless the comparison is ``==`` or ``!=``. The latter cases return
:const:`False` or :const:`True`, respectively.
In Boolean contexts, all :class:`date` objects are considered to be true.
Instance methods:
.. method:: date.replace(year=self.year, month=self.month, day=self.day)
Return a date with the same value, except for those parameters given new
values by whichever keyword arguments are specified.
Example::
>>> from datetime import date
>>> d = date(2002, 12, 31)
>>> d.replace(day=26)
datetime.date(2002, 12, 26)
:class:`date` objects are also supported by generic function
:func:`copy.replace`.
.. method:: date.timetuple()
Return a :class:`time.struct_time` such as returned by :func:`time.localtime`.
The hours, minutes and seconds are 0, and the DST flag is -1.
``d.timetuple()`` is equivalent to::
time.struct_time((d.year, d.month, d.day, 0, 0, 0, d.weekday(), yday, -1))
where ``yday = d.toordinal() - date(d.year, 1, 1).toordinal() + 1``
is the day number within the current year starting with ``1`` for January 1st.
.. method:: date.toordinal()
Return the proleptic Gregorian ordinal of the date, where January 1 of year 1
has ordinal 1. For any :class:`date` object *d*,
``date.fromordinal(d.toordinal()) == d``.
.. method:: date.weekday()
Return the day of the week as an integer, where Monday is 0 and Sunday is 6.
For example, ``date(2002, 12, 4).weekday() == 2``, a Wednesday. See also
:meth:`isoweekday`.
.. method:: date.isoweekday()
Return the day of the week as an integer, where Monday is 1 and Sunday is 7.
For example, ``date(2002, 12, 4).isoweekday() == 3``, a Wednesday. See also
:meth:`weekday`, :meth:`isocalendar`.
.. method:: date.isocalendar()
Return a :term:`named tuple` object with three components: ``year``,
``week`` and ``weekday``.
The ISO calendar is a widely used variant of the Gregorian calendar. [#]_
The ISO year consists of 52 or 53 full weeks, and where a week starts on a
Monday and ends on a Sunday. The first week of an ISO year is the first
(Gregorian) calendar week of a year containing a Thursday. This is called week
number 1, and the ISO year of that Thursday is the same as its Gregorian year.
For example, 2004 begins on a Thursday, so the first week of ISO year 2004
begins on Monday, 29 Dec 2003 and ends on Sunday, 4 Jan 2004::
>>> from datetime import date
>>> date(2003, 12, 29).isocalendar()
datetime.IsoCalendarDate(year=2004, week=1, weekday=1)
>>> date(2004, 1, 4).isocalendar()
datetime.IsoCalendarDate(year=2004, week=1, weekday=7)
.. versionchanged:: 3.9
Result changed from a tuple to a :term:`named tuple`.
.. method:: date.isoformat()
Return a string representing the date in ISO 8601 format, ``YYYY-MM-DD``::
>>> from datetime import date
>>> date(2002, 12, 4).isoformat()
'2002-12-04'
.. method:: date.__str__()
For a date *d*, ``str(d)`` is equivalent to ``d.isoformat()``.
.. method:: date.ctime()
Return a string representing the date::
>>> from datetime import date
>>> date(2002, 12, 4).ctime()
'Wed Dec 4 00:00:00 2002'
``d.ctime()`` is equivalent to::
time.ctime(time.mktime(d.timetuple()))
on platforms where the native C
:c:func:`ctime` function (which :func:`time.ctime` invokes, but which
:meth:`date.ctime` does not invoke) conforms to the C standard.
.. method:: date.strftime(format)
Return a string representing the date, controlled by an explicit format string.
Format codes referring to hours, minutes or seconds will see 0 values.
See also :ref:`strftime-strptime-behavior` and :meth:`date.isoformat`.
.. method:: date.__format__(format)
Same as :meth:`.date.strftime`. This makes it possible to specify a format
string for a :class:`.date` object in :ref:`formatted string
literals <f-strings>` and when using :meth:`str.format`.
See also :ref:`strftime-strptime-behavior` and :meth:`date.isoformat`.
Examples of Usage: :class:`date`
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Example of counting days to an event::
>>> import time
>>> from datetime import date
>>> today = date.today()
>>> today
datetime.date(2007, 12, 5)
>>> today == date.fromtimestamp(time.time())
True
>>> my_birthday = date(today.year, 6, 24)
>>> if my_birthday < today:
... my_birthday = my_birthday.replace(year=today.year + 1)
...
>>> my_birthday
datetime.date(2008, 6, 24)
>>> time_to_birthday = abs(my_birthday - today)
>>> time_to_birthday.days
202
More examples of working with :class:`date`:
.. doctest::
>>> from datetime import date
>>> d = date.fromordinal(730920) # 730920th day after 1. 1. 0001
>>> d
datetime.date(2002, 3, 11)
>>> # Methods related to formatting string output
>>> d.isoformat()
'2002-03-11'
>>> d.strftime("%d/%m/%y")
'11/03/02'
>>> d.strftime("%A %d. %B %Y")
'Monday 11. March 2002'
>>> d.ctime()
'Mon Mar 11 00:00:00 2002'
>>> 'The {1} is {0:%d}, the {2} is {0:%B}.'.format(d, "day", "month")
'The day is 11, the month is March.'
>>> # Methods for to extracting 'components' under different calendars
>>> t = d.timetuple()
>>> for i in t: # doctest: +SKIP
... print(i)
2002 # year
3 # month
11 # day
0
0
0
0 # weekday (0 = Monday)
70 # 70th day in the year
-1
>>> ic = d.isocalendar()
>>> for i in ic: # doctest: +SKIP
... print(i)
2002 # ISO year
11 # ISO week number
1 # ISO day number ( 1 = Monday )
>>> # A date object is immutable; all operations produce a new object
>>> d.replace(year=2005)
datetime.date(2005, 3, 11)
.. _datetime-datetime:
: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.
Constructor:
.. class:: datetime(year, month, day, hour=0, minute=0, second=0, microsecond=0, tzinfo=None, *, fold=0)
The *year*, *month* and *day* arguments are required. *tzinfo* may be ``None``, or an
instance of a :class:`tzinfo` subclass. The remaining arguments must be integers
in the following ranges:
* ``MINYEAR <= year <= MAXYEAR``,
* ``1 <= month <= 12``,
* ``1 <= day <= number of days in the given month and year``,
* ``0 <= hour < 24``,
* ``0 <= minute < 60``,
* ``0 <= second < 60``,
* ``0 <= microsecond < 1000000``,
* ``fold in [0, 1]``.
If an argument outside those ranges is given, :exc:`ValueError` is raised.
.. versionadded:: 3.6
Added the ``fold`` argument.
Other constructors, all class methods:
.. classmethod:: datetime.today()
Return the current local datetime, with :attr:`.tzinfo` ``None``.
Equivalent to::
datetime.fromtimestamp(time.time())
See also :meth:`now`, :meth:`fromtimestamp`.
This method is functionally equivalent to :meth:`now`, but without a
``tz`` parameter.
.. classmethod:: datetime.now(tz=None)
Return the current local date and time.
If optional argument *tz* is ``None``
or not specified, this is like :meth:`today`, but, if possible, supplies more
precision than can be gotten from going through a :func:`time.time` timestamp
(for example, this may be possible on platforms supplying the C
:c:func:`gettimeofday` function).
If *tz* is not ``None``, it must be an instance of a :class:`tzinfo` subclass,
and the current date and time are converted to *tz*’s time zone.
This function is preferred over :meth:`today` and :meth:`utcnow`.
.. classmethod:: datetime.utcnow()
Return the current UTC date and time, with :attr:`.tzinfo` ``None``.
This is like :meth:`now`, but returns the current UTC date and time, as a naive
:class:`.datetime` object. An aware current UTC datetime can be obtained by
calling ``datetime.now(timezone.utc)``. See also :meth:`now`.
.. warning::
Because naive ``datetime`` objects are treated by many ``datetime`` methods
as local times, it is preferred to use aware datetimes to represent times
in UTC. As such, the recommended way to create an object representing the
current time in UTC is by calling ``datetime.now(timezone.utc)``.
.. deprecated:: 3.12
Use :meth:`datetime.now` with :attr:`UTC` instead.
.. classmethod:: datetime.fromtimestamp(timestamp, tz=None)
Return the local date and time corresponding to the POSIX timestamp, such as is
returned by :func:`time.time`. If optional argument *tz* is ``None`` or not
specified, the timestamp is converted to the platform's local date and time, and
the returned :class:`.datetime` object is naive.
If *tz* is not ``None``, it must be an instance of a :class:`tzinfo` subclass, and the
timestamp is converted to *tz*’s time zone.
:meth:`fromtimestamp` may raise :exc:`OverflowError`, if the timestamp is out of
the range of values supported by the platform C :c:func:`localtime` or
:c:func:`gmtime` functions, and :exc:`OSError` on :c:func:`localtime` or
:c:func:`gmtime` failure.
It's common for this to be restricted to years in
1970 through 2038. Note that on non-POSIX systems that include leap seconds in
their notion of a timestamp, leap seconds are ignored by :meth:`fromtimestamp`,
and then it's possible to have two timestamps differing by a second that yield
identical :class:`.datetime` objects. This method is preferred over
:meth:`utcfromtimestamp`.
.. versionchanged:: 3.3
Raise :exc:`OverflowError` instead of :exc:`ValueError` if the timestamp
is out of the range of values supported by the platform C
:c:func:`localtime` or :c:func:`gmtime` functions. Raise :exc:`OSError`
instead of :exc:`ValueError` on :c:func:`localtime` or :c:func:`gmtime`
failure.
.. versionchanged:: 3.6
:meth:`fromtimestamp` may return instances with :attr:`.fold` set to 1.
.. classmethod:: datetime.utcfromtimestamp(timestamp)
Return the UTC :class:`.datetime` corresponding to the POSIX timestamp, with
:attr:`.tzinfo` ``None``. (The resulting object is naive.)
This may raise :exc:`OverflowError`, if the timestamp is
out of the range of values supported by the platform C :c:func:`gmtime` function,
and :exc:`OSError` on :c:func:`gmtime` failure.
It's common for this to be restricted to years in 1970 through 2038.
To get an aware :class:`.datetime` object, call :meth:`fromtimestamp`::
datetime.fromtimestamp(timestamp, timezone.utc)
On the POSIX compliant platforms, it is equivalent to the following
expression::
datetime(1970, 1, 1, tzinfo=timezone.utc) + timedelta(seconds=timestamp)
except the latter formula always supports the full years range: between
:const:`MINYEAR` and :const:`MAXYEAR` inclusive.
.. warning::
Because naive ``datetime`` objects are treated by many ``datetime`` methods
as local times, it is preferred to use aware datetimes to represent times
in UTC. As such, the recommended way to create an object representing a
specific timestamp in UTC is by calling
``datetime.fromtimestamp(timestamp, tz=timezone.utc)``.
.. versionchanged:: 3.3
Raise :exc:`OverflowError` instead of :exc:`ValueError` if the timestamp
is out of the range of values supported by the platform C
:c:func:`gmtime` function. Raise :exc:`OSError` instead of
:exc:`ValueError` on :c:func:`gmtime` failure.
.. deprecated:: 3.12
Use :meth:`datetime.fromtimestamp` with :attr:`UTC` instead.
.. classmethod:: datetime.fromordinal(ordinal)
Return the :class:`.datetime` corresponding to the proleptic Gregorian ordinal,
where January 1 of year 1 has ordinal 1. :exc:`ValueError` is raised unless ``1
<= ordinal <= datetime.max.toordinal()``. The hour, minute, second and
microsecond of the result are all 0, and :attr:`.tzinfo` is ``None``.
.. classmethod:: datetime.combine(date, time, tzinfo=time.tzinfo)
Return a new :class:`.datetime` object whose date components are equal to the
given :class:`date` object's, and whose time components
are equal to the given :class:`.time` object's. If the *tzinfo*