THRIFT-5693 - fix bug in serialization of enum default values

[andrewcunnin]

This change fixes a bug where the default values set in enum fields were unable to be serialized. Previously default enum values were being stored as enum objects upon initialization, where Thrift generally expects I32 values. With the changes in this pull request, serialization and deserialization are fixed and the python 3.4 style enums continue to work as expected.

JIRA ticket here: https://issues.apache.org/jira/browse/THRIFT-5693

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[fishy]

we actually don't have python set up in github actions yet so this is not really tested (we only tested that it did not break other languages that's setup in github actions)

can you show the diff between old and new compiler generated python code?

[andrewcunnin]

Gotcha, here's a diff of the ThriftTest.thrift generated Python: https://gist.github.com/andrewcunnin/802f4d8fa779c181e2272b5219b52a07

[andrewcunnin]

For the testing, is running the cross test and running make -k check in test/py sufficient? Or were you referring to a different set of tests that I should be running separately?

[fishy]

For the testing, is running the cross test and running make -k check in test/py sufficient? Or were you referring to a different set of tests that I should be running separately?

we have tests under both test/py and lib/py/test, and then we also have cross tests between different language libraries.