After upgrading to Python 3.13, I'm not able to run mailman3 any more. Reproducible: Always Steps to Reproduce: 1.sudo -u mailman mailman3 conf (The regular service also fails to start, but this is a simple command-line reproducer.) Actual Results: A backtrace ending in File "/usr/lib/python3.13/site-packages/mailman/commands/cli_gatenews.py", line 24, in <module> import nntplib ModuleNotFoundError: No module named 'nntplib' Expected Results: A printout of the configuration. "nntplib" is imported in mailman/commands/cli_gatenews.py, but the "nntplib" library is removed in Python 3.13. I'm not the first to discover this as there is an upstreams bug https://gitlab.com/mailman/mailman/-/issues/1176 but I couldn't find any report here in Bugzilla.
Oof. Thanks for reporting!
From the spec file: # Tests fail with nspawn mock due to lack of access to /dev/stdout # TODO: Figure out a fix for this venv/bin/python -m nose2 -v || : From the build log: ====================================================================== ERROR: mailman.commands.tests.test_cli_gatenews (nose2.loader.ModuleImportFailure.mailman.commands.tests.test_cli_gatenews) ---------------------------------------------------------------------- ImportError: Failed to import test module: mailman.commands.tests.test_cli_gatenews Traceback (most recent call last): File "/usr/lib/python3.13/site-packages/nose2/plugins/loader/discovery.py", line 195, in _find_tests_in_file module = util.module_from_name(module_name) File "/usr/lib/python3.13/site-packages/nose2/util.py", line 73, in module_from_name __import__(name) ~~~~~~~~~~^^^^^^ File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/commands/tests/test_cli_gatenews.py", line 21, in <module> import nntplib ModuleNotFoundError: No module named 'nntplib' ====================================================================== ERROR: test_opening_character_device (mailman.core.tests.test_logging.TestRunner.test_opening_character_device) ---------------------------------------------------------------------- Traceback (most recent call last): File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/core/tests/test_logging.py", line 28, in test_opening_character_device handler = ReopenableFileHandler('test', '/dev/stdout') File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/core/logging.py", line 51, in __init__ self._stream = self._open() ~~~~~~~~~~^^ File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/core/logging.py", line 64, in _open return codecs.open(self.filename, open_mode, 'utf-8') ~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "<frozen codecs>", line 921, in open PermissionError: [Errno 13] Permission denied: '/dev/stdout' ====================================================================== ERROR: mailman.runners.tests.test_nntp (nose2.loader.ModuleImportFailure.mailman.runners.tests.test_nntp) ---------------------------------------------------------------------- ImportError: Failed to import test module: mailman.runners.tests.test_nntp Traceback (most recent call last): File "/usr/lib/python3.13/site-packages/nose2/plugins/loader/discovery.py", line 195, in _find_tests_in_file module = util.module_from_name(module_name) File "/usr/lib/python3.13/site-packages/nose2/util.py", line 73, in module_from_name __import__(name) ~~~~~~~~~~^^^^^^ File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/runners/tests/test_nntp.py", line 21, in <module> import nntplib ModuleNotFoundError: No module named 'nntplib' ====================================================================== ERROR: LayerSuite ---------------------------------------------------------------------- Traceback (most recent call last): File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/testing/layers.py", line 135, in setUp initialize.initialize_2(testing=True) ~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^ File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/core/initialize.py", line 199, in initialize_2 initialize_commands() ~~~~~~~~~~~~~~~~~~~^^ File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/app/commands.py", line 29, in initialize add_components('commands', IEmailCommand, config.commands) ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/utilities/modules.py", line 218, in add_components for component_class in find_pluggable_components(subpackage, interface): ~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^ File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/utilities/modules.py", line 177, in find_pluggable_components yield from find_components('mailman.' + subpackage, interface) File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/utilities/modules.py", line 150, in find_components module = import_module(module_name) File "/usr/lib64/python3.13/importlib/__init__.py", line 88, in import_module return _bootstrap._gcd_import(name[level:], package, level) ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "<frozen importlib._bootstrap>", line 1387, in _gcd_import File "<frozen importlib._bootstrap>", line 1360, in _find_and_load File "<frozen importlib._bootstrap>", line 1331, in _find_and_load_unlocked File "<frozen importlib._bootstrap>", line 935, in _load_unlocked File "<frozen importlib._bootstrap_external>", line 1026, in exec_module File "<frozen importlib._bootstrap>", line 488, in _call_with_frames_removed File "/builddir/build/BUILD/mailman3-3.3.9-build/mailman-3.3.9/src/mailman/commands/cli_gatenews.py", line 24, in <module> import nntplib ModuleNotFoundError: No module named 'nntplib' ---------------------------------------------------------------------- Ran 53 tests in 0.275s FAILED (errors=4) ------------------ I believe the original reason for ignoring the test results is no longer valid. If this was not ignored, we would have known about this problem a year ago. Please don't do that. This is explicitly forbidden by the guidelines https://docs.fedoraproject.org/en-US/packaging-guidelines/Python/#_running_tests -- exactly for this reason.
If you don't actually need NNTP support, the easiest way to get on your way is to add [runner.nntp] start: no to your mailman.cfg file, and to create an empty file /usr/lib/python3.13/site-packages/nntplib.py This is not a fix, this is a workaround.
Thanks for that workaround! I helps me, and I suspect potentially many others.