A datetime object d is aware if d.tzinfo is not None and
d.tzinfo.utcoffset(d) does  not return None. If d.tzinfo is None,
or if d.tzinfo is not None but d.tzinfo.utcoffset(d) returns None,
 d is naive.

This commit ensures that instances with non-None d.tzinfo, but
d.tzinfo.utcoffset(d) returning None are treated as naive.

In addition, C acceleration code will raise TypeError if
d.tzinfo.utcoffset(d) returns an object with the type other than
timedelta.

* Updated the documentation.

Assume that the term "naive" is defined elsewhere and remove the
not entirely correct clarification.  Thanks, Tim.

Since implementation of bpo-25283, the objects returned by time.localtime
always have tm_zone and tm_gmtoff attributes.  Remove code that
anticipates their absence.

Closes bpo-15873.

* Closes issue bpo-5288: Allow tzinfo objects with sub-minute offsets.

* bpo-5288: Implemented %z formatting of sub-minute offsets.

* bpo-5288: Removed mentions of the whole minute limitation on TZ offsets.

* bpo-5288: Removed one more mention of the whole minute limitation.

Thanks @csabella!

* Fix a formatting error in the docs

* Addressed review comments.

Thanks, @haypo.

Only C implementation was tested.

* Revert "bpo-30854: Fix compile error when --without-threads (#2581)"

This reverts commit 0c311630.

* Revert "NEWS for 30777 (#2576)"

This reverts commit aaa917ff.

* Revert "bpo-21624: IDLE -- minor htest fixes (#2575)"

This reverts commit 2000150c.

* Revert "bpo-30777: IDLE: configdialog - add docstrings and improve comments (#2440)"

This reverts commit 7eb5883a.

* Revert "bpo-30319: socket.close() now ignores ECONNRESET (#2565)"

This reverts commit 67e1478d.

* Revert "bpo-30789: Use a single memory block for co_extra. (#2555)"

This reverts commit 378ebb65.

* Revert "bpo-30845: Enhance test_concurrent_futures cleanup (#2564)"

This reverts commit 3df9dec4.

* Revert "bpo-29293: multiprocessing.Condition.notify() lacks parameter `n` (#2480)"

This reverts commit 48350412.

* Revert "Remove outdated FOX from GUI FAQ (GH-2538)"

This reverts commit d3ed2877.

* Revert "bpo-6691: Pyclbr now reports nested classes and functions. (#2503)"

This reverts commit 246ff3bd.

* Revert "bpo-29464: Rename METH_FASTCALL to METH_FASTCALL|METH_KEYWORDS and make (#1955)"

This reverts commit 6969eaf4.

* Revert "bpo-30832: Remove own implementation for thread-local storage (#2537)"

This reverts commit aa0aa049.

* Revert "bpo-30764: Fix regrtest --fail-env-changed --forever (#2536)"

This reverts commit 5e87592f.

* Revert "bpo-30822: Deduplicate ZoneInfoTest classes in test_datetime. (#2534)"

This reverts commit 34b54873.

* Revert "bpo-30822: Fix testing of datetime module. (#2530)"

This reverts commit 98b6bc3b.

Only C implementation was tested.

The default value of fold is zero, not True. Fix the docstring of the Python
implementation.

Based on patch by Ville Skyttä.

Added an optional argument timespec to the datetime isoformat() method
to choose the precision of the time component.

Original patch by Alessandro Cucci.

Permission was validated prior to adding these markings.

of datetime.datetime: microseconds are now rounded to nearest with ties going
to nearest even integer (ROUND_HALF_EVEN), instead of being rounding towards
zero (ROUND_DOWN). It's important that these methods use the same rounding
mode than datetime.timedelta to keep the property:

   (datetime(1970,1,1) + timedelta(seconds=t)) == datetime.utcfromtimestamp(t)

It also the rounding mode used by round(float) for example.

Add more unit tests on the rounding mode in test_datetime.

remove scories of round half up code and debug code.

datetime.datetime now round microseconds to nearest with ties going to nearest
even integer (ROUND_HALF_EVEN), as round(float), instead of rounding towards
-Infinity (ROUND_FLOOR).

pytime API: replace _PyTime_ROUND_HALF_UP with _PyTime_ROUND_HALF_EVEN. Fix
also _PyTime_Divide() for negative numbers.

_PyTime_AsTimeval_impl() now reuses _PyTime_Divide() instead of reimplementing
rounding modes.

"""Issue #23517: datetime.timedelta constructor now rounds microseconds to
nearest with ties going away from zero (ROUND_HALF_UP), as Python 2 and Python
older than 3.3, instead of rounding to nearest with ties going to nearest even
integer (ROUND_HALF_EVEN)."""

datetime.timedelta uses rounding mode ROUND_HALF_EVEN again.

datetime.datetime.fromtimestamp() and datetime.datetime.utcfromtimestamp().
microseconds sign should be kept before rounding.

datetime.datetime now round microseconds to nearest with ties going away from
zero (ROUND_HALF_UP), as Python 2 and Python older than 3.3, instead of
rounding towards -Infinity (ROUND_FLOOR).

with ties going away from zero (ROUND_HALF_UP), as Python 2 and Python older
than 3.3, instead of rounding to nearest with ties going to nearest even
integer (ROUND_HALF_EVEN).

Fixed 2 to 3 porting bug in pynche.ColorDB.

Original patch by Akira Li.

 * Eliminated OverflowError from timedelta * float for some floats;
 * Corrected rounding in timedlta true division.

implementation in issue #21408 they are redundant.

This patch brings the pure-python datetime more in-line with the C
module.  Patch contributed by Brian Kearns, a PyPy developer.  PyPy
project has been running these modifications in PyPy2 stdlib.

This commit includes:

- General PEP8/cleanups;
- Better testing of argument types passed to constructors;
- Removal of duplicate operations;
- Optimization of timedelta creation;
- Caching the result of __hash__ like the C accelerator;
- Enhancements/bug fixes in tests.

class name instead of hardcoded one.

error messages and comments.

ModuleNotFoundError.