Fixed deprecated access of collections members.

[NeilGirdhar]

Changed the access of the abstract base classes to use collections.abc.
This prevents warnings in Python 3.7, and runtime errors in Python 3.8+.

[NeilGirdhar]

Closes #26095

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[NeilGirdhar]

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[NeilGirdhar]

If there are problems importing collections.abc on older Python, it would be helpful to either push this through (benjaminp/six#241) or else use this:

try:
    import collections.abc as collections_abc # only works on python 3.3+
except ImportError:
    import collections as collections_abc

[alextp]

@NeilGirdhar can you change the pull request to do your proposed workaround for older python versions? TensorFlow still has to support python 2.7 and 3.5

[NeilGirdhar]

@alextp can we rely on six if they push through this pull request? benjaminp/six#241

3.5 is no problem. collections.abc exists there.

[alextp]

Yes, relying on six would be ideal. We can also put this in https://github.com/tensorflow/tensorflow/blob/master/tensorflow/python/util/compat.py and import from there

…

On Mon, Mar 4, 2019 at 12:06 PM Neil ***@***.***> wrote: @alextp <https://github.com/alextp> can we rely on six if they push through this pull request? benjaminp/six#241 <benjaminp/six#241> — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#26173 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAATxb4uSavXm7V2iYroJq5jW8jkr19Cks5vTXzVgaJpZM4bUt-U> .

-- - Alex

[NeilGirdhar]

I don't understand these build errors. It seems to be totally unrelated to my change. Any ideas?

[NeilGirdhar]

@rthadur Could these errors have something to do with how the tests were run?

[rthadur]

@NeilGirdhar i believe you need to update the test cases which are associated with the files.

[NeilGirdhar]

@rthadur I don't see that? I see errors like "Broken by missing target @com_google_absl//absl/base:base" ? I don't see how this relates...

[rthadur]

@alextp any thoughts why this tests are failing ?

[alextp]

@rthadur Looked like a tool failure, retrying

[rthadur]

@rthadur Looked like a tool failure, retrying

@alextp thank you, seems like most of the test failures are gone, can you please approve again.

[rthadur]

can you please above error

[rthadur]

tensorflow/python/util/protobuf/compare.py", line 75, in
from tensorflow.python.util.compat import collections_abc
ImportError: No module named tensorflow.python.util.compat

[NeilGirdhar]

I've replaced this line with a relative import, and fixed some merge conflicts.