Segfault in test shutdown with specific module

[mrbean-bremen]

I accidentally stumbled over an issue related to pyfakefs if running it with opentimelineio code.

With the following code (copied from the issue):

import opentimelineio as otio

# Does not segfault if you comment out this "test"
def test_empty_fs(fs):
    pass


def test_create_clip():
    # can be child classes of SerializableObjectWithMetadata (Clip, Gap, etc),
    # however other otio C++ classes appear to be ok (RationalTime, TimeRange,
    # TimeTransform)
    otio.core.SerializableObjectWithMetadata(
        # also does not segfault if you comment this out
        metadata={}
    )

If running this, a segmentation fault occurs on test shutdown, and with Python versions >=3.10 an additional error is shown:

Fatal Python error: PyThreadState_Get: the function must be called with the GIL held, but the GIL is released (the current Python thread state is NULL)
Python runtime state: finalizing (tstate=0x00000208960683d0)

I can reproduce this on all systems (Windows, Linux, MacOS) in the CI, with different Python and Pytest versions (except for Python 3.7 with Pytest versions from 4.6 to 5.3, for some reason).

I currently have no idea what causes this, but is seems to have something to do with the cache.

[mrbean-bremen]

Closing as handled - shall be reopened if a similar issue comes up again.