missing attibute '_is_main_interpreter' (python 3.9 support) #604
Description
Downstream bug: https://bugzilla.redhat.com/show_bug.cgi?id=1794283
Currently building with python3.9 prereleases works, but tests fail.
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Traceback (most recent call last):
File "/builddir/build/BUILD/eventlet-0.25.1/tests/isolated/greendns_from_address_203.py", line 6, in <module>
eventlet.monkey_patch(all=True)
File "/builddir/build/BUILD/eventlet-0.25.1/eventlet/patcher.py", line 285, in monkey_patch
modules_to_patch += modules_function()
File "/builddir/build/BUILD/eventlet-0.25.1/eventlet/patcher.py", line 435, in _green_thread_modules
from eventlet.green import threading
File "/builddir/build/BUILD/eventlet-0.25.1/eventlet/green/threading.py", line 22, in <module>
eventlet.patcher.inject(
File "/builddir/build/BUILD/eventlet-0.25.1/eventlet/patcher.py", line 100, in inject
module = __import__(module_name, {}, {}, module_name.split('.')[:-1])
File "/usr/lib64/python3.9/threading.py", line 37, in <module>
_is_main_interpreter = _thread._is_main_interpreter
AttributeError: module 'eventlet.green.thread' has no attribute '_is_main_interpreter'
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FAIL
This was apparently added in https://bugs.python.org/issue37266
(A bunch of the other tests also fail the same way, full list can be seen in: https://download.copr.fedorainfracloud.org/results/@python/python3.9/fedora-rawhide-x86_64/01309177-python-eventlet/build.log.gz