Python flake: //src/python/grpcio_tests/tests/unit:_abort_test

[rmstar]

FAIL: //src/python/grpcio_tests/tests/unit:_abort_test (see /root/.cache/bazel/_bazel_root/d2dc70c3d9da3fab488ba0dcbbd35051/execroot/com_github_grpc_grpc/bazel-out/k8-fastbuild/testlogs/src/python/grpcio_tests/tests/unit/_abort_test/test.log)
INFO: From Testing //src/python/grpcio_tests/tests/unit:_abort_test:
==================== Test output for //src/python/grpcio_tests/tests/unit:_abort_test:
test_abort (__main__.AbortTest) ... ok
test_abort_does_not_leak_local_vars (__main__.AbortTest) ... FAIL
test_abort_with_status (__main__.AbortTest) ... ok
test_invalid_code (__main__.AbortTest) ... ok
======================================================================
FAIL: test_abort_does_not_leak_local_vars (__main__.AbortTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/root/.cache/bazel/_bazel_root/d2dc70c3d9da3fab488ba0dcbbd35051/execroot/com_github_grpc_grpc/bazel-out/k8-fastbuild/bin/src/python/grpcio_tests/tests/unit/_abort_test.runfiles/com_github_grpc_grpc/src/python/grpcio_tests/tests/unit/_abort_test.py", line 130, in test_abort_does_not_leak_local_vars
    self.assertIsNone(weak_ref())
AssertionError: <__main__._Object object at 0x7fc0eee5bd50> is not None
----------------------------------------------------------------------
Ran 4 tests in 0.116s
FAILED (failures=1)

https://source.cloud.google.com/results/invocations/be75aace-e7dc-4792-ac51-caa33b9f3457/targets/grpc%2Fcore%2Fpull_request%2Flinux%2Fgrpc_python_bazel_test/log

Seen on PR: #17895

[ericgribkoff]

I just merged #17929 which might fix this, but I suspect there's some other issue at hand. Will monitor to see if the test continues to be flaky.

[gnossen]

This error hasn't shown up in Fusion for the past ten days. Closing.

[stanley-cheung]

FYI I have just seen this in another PR #17862: https://source.cloud.google.com/results/invocations/fde1759a-6f78-4f43-9e02-c59d86505a1c/targets/github%2Fgrpc%2Fpython_linux_opt_native/tests