Python3.13 logging level not working

[trivialkettle]

Bug description:

Hi,
i noticed a regression in python 3.13.2 that the log level has no effect.
I tested the example from https://docs.python.org/3.13/library/logging.html

import logging
logger = logging.getLogger(__name__)

def main():
    logging.basicConfig(filename='myapp.log', level=logging.INFO)
    logger.info('Started')
    logger.info('Finished')

if __name__ == '__main__':
    main()

python3.13 example.py 

but nothing is printed.

CPython versions tested on:

3.13

Operating systems tested on:

Linux

Linked PRs

• gh-131791: Improve speed of textwrap.dedent by replacing re #131792

[graingert]

you configured logging.basicConfig(filename='myapp.log', level=logging.INFO) this means nothing will be printed, instead logs will be written to myapp.log

[ericvsmith]

As @graingert mentions, the output does show up in the file myapp.log.

If this is a regression, then in what version of python did it produce output?

I don't think there's a bug here, but if this did behave differently in a previous version of python that would be interesting.

[trivialkettle]

Ah sorry, you are right, I missed this.

I had some strange issues, that I could not set the logger level, my code works on python 3.10 but not on 3.13.

basically I do

    logging.basicConfig(stream=sys.stderr, level=args.log, format="%(asctime)s:" + logging.BASIC_FORMAT)
...
    class Foo:
        self._logger = logging.getLogger(self.__module__)

    def foo():
        self._logger.debug("foo")

I try to reproduce this, maybe it was a glitch or something.

Edit: I close it for now until I can reproduce this.