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pytz - World Timezone Definitions for Python
============================================
:Author: Stuart Bishop
Introduction
~~~~~~~~~~~~
pytz brings the Olson tz database into Python. This library allows
accurate and cross platform timezone calculations using Python 2.4
or higher. It also solves the issue of ambiguous times at the end
of daylight saving time, which you can read more about in the Python
Library Reference (``datetime.tzinfo``).
Almost all of the Olson timezones are supported.
.. note::
Projects using Python 3.9 or later should be using the support
now included as part of the standard library, and third party
packages work with it such as [tzdata].
pytz offers no advantages beyond backwards compatibility with
code written for earlier versions of Python.
.. note::
This library differs from the documented Python API for
tzinfo implementations; if you want to create local wallclock
times you need to use the ``localize()`` method documented in this
document. In addition, if you perform date arithmetic on local
times that cross DST boundaries, the result may be in an incorrect
timezone (ie. subtract 1 minute from 2002-10-27 1:00 EST and you get
2002-10-27 0:59 EST instead of the correct 2002-10-27 1:59 EDT). A
``normalize()`` method is provided to correct this. Unfortunately these
issues cannot be resolved without modifying the Python datetime
implementation (see PEP-431).
Installation
~~~~~~~~~~~~
This package can either be installed using pip or from a tarball using the
standard Python distutils.
If you are installing using pip, you don't need to download anything as the
latest version will be downloaded for you from PyPI::
pip install pytz
If you are installing from a tarball, run the following command as an
administrative user::
python setup.py install
pytz for Enterprise
~~~~~~~~~~~~~~~~~~~
Available as part of the Tidelift Subscription.
The maintainers of pytz and thousands of other packages are working with
Tidelift to deliver commercial support and maintenance for the open source
dependencies you use to build your applications. Save time, reduce risk,
and improve code health, while paying the maintainers of the exact
dependencies you use. `Learn more.
`_.
Example & Usage
~~~~~~~~~~~~~~~
Localized times and date arithmetic
-----------------------------------
>>> from datetime import datetime, timedelta
>>> from pytz import timezone
>>> import pytz
>>> utc = pytz.utc
>>> utc.zone
'UTC'
>>> eastern = timezone('US/Eastern')
>>> eastern.zone
'US/Eastern'
>>> amsterdam = timezone('Europe/Amsterdam')
>>> fmt = '%Y-%m-%d %H:%M:%S %Z%z'
This library only supports two ways of building a localized time. The
first is to use the ``localize()`` method provided by the pytz library.
This is used to localize a naive datetime (datetime with no timezone
information):
>>> loc_dt = eastern.localize(datetime(2002, 10, 27, 6, 0, 0))
>>> print(loc_dt.strftime(fmt))
2002-10-27 06:00:00 EST-0500
The second way of building a localized time is by converting an existing
localized time using the standard ``astimezone()`` method:
>>> ams_dt = loc_dt.astimezone(amsterdam)
>>> ams_dt.strftime(fmt)
'2002-10-27 12:00:00 CET+0100'
Unfortunately using the tzinfo argument of the standard datetime
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