bpo-39723: make io.open_code accept PathLike objects

[hauntsaninja]

https://bugs.python.org/issue39723

[codecov]

Codecov Report

Merging #18602 into master will decrease coverage by 0.13%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #18602      +/-   ##
==========================================
- Coverage   82.20%   82.06%   -0.14%     
==========================================
  Files        1958     1955       -3     
  Lines      589743   584072    -5671     
  Branches    44457    44458       +1     
==========================================
- Hits       484772   479324    -5448     
+ Misses      95308    95117     -191     
+ Partials     9663     9631      -32     

Impacted Files	Coverage Δ
Lib/distutils/tests/test_bdist_rpm.py	30.00% <0.00%> (-65.00%)	⬇️
Lib/distutils/command/bdist_rpm.py	7.63% <0.00%> (-56.88%)	⬇️
Modules/_decimal/libmpdec/umodarith.h	80.76% <0.00%> (-19.24%)	⬇️
Lib/test/test_urllib2net.py	76.92% <0.00%> (-13.85%)	⬇️
Lib/test/test_smtpnet.py	78.57% <0.00%> (-12.86%)	⬇️
Lib/ftplib.py	63.85% <0.00%> (-6.06%)	⬇️
Lib/test/test_ftplib.py	87.11% <0.00%> (-4.72%)	⬇️
Tools/scripts/db2pickle.py	17.82% <0.00%> (-3.97%)	⬇️
Tools/scripts/pickle2db.py	16.98% <0.00%> (-3.78%)	⬇️
Lib/test/test_socket.py	71.94% <0.00%> (-3.87%)	⬇️
... and 336 more

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[lazka]

Where does the new reference returned by PyOS_FSPath() get freed?

[hauntsaninja]

Thanks, hopefully in this next commit :-)

[tirkarthi]

io.open_code shouldn't be accepting path-like objects as noted in https://bugs.python.org/msg362522 . I would propose closing this PR and opening another one for documentation update as @zooba suggested.

[hauntsaninja]

Sounds good, opened #19824 for the documentation update.