Issue #15301: Parsing fd, uid, and gid parameters for builtins
in Modules/posixmodule.c is now far more robust.
#18273: move the tests in Lib/test/json_tests to Lib/test/test_json and make them discoverable by unittest.  Patch by Zachary Ware.
#18273: merge with 3.3.
#18267: make whitespace consistent and fix an operator.
#18267: merge with 3.3.
Fix a typo in PyUnicode_CopyCharacters() documentation.
Fix a typo in PyUnicode_CopyCharacters() documentation.
#18581: remove duplicate test and run a test class that was skipped.  Initial patch by Vajrasky Kok.
#18581: merge with 3.3.
#18357: add tests for dictview set difference.  Patch by Fraser Tweedale.
#18357: merge with 3.3.
Closes #18671: Output more information when logging exceptions occur.
#18600: add policy to add_string, and as_bytes and __bytes__ methods.

This was triggered by wanting to make the doctest in email.policy.rst pass;
as_bytes and __bytes__ are clearly useful now that we have BytesGenerator.
Also updated the Message docs to document the policy keyword that was
added in 3.3.
#18600: In 3.3, as_string does not accept a policy keyword.

Also, document the policy keyword that was added to Message in 3.3.
Null merge related to #18600.

For 3.3, we just deleted the example.  In 3.4 it was fixed.
Issue #18668: Further clarify m_size setting for non-negative values
Issue #18668: Further clarify m_size setting for non-negative values
Issue #16400: Add command line option for isolated mode.

 -I

    Run Python in isolated mode. This also implies -E and -s. In isolated mode
    sys.path contains neither the script?s directory nor the user?s
    site-packages directory. All PYTHON* environment variables are ignored,
    too. Further restrictions may be imposed to prevent the user from
    injecting malicious code.
typo, changeset dd0d751cc7f1 belongs to issue #16499 not issue #16400
Issue #15651: PEP 3121 refactoring for _elementtree

Patch by Antoine Pitrou (based on Robin Schreiber's original patch)