Running Picard in debug mode outputs 2 similar log lines on console.
D: 23:15:34,394 /home/zas/src/picard/picard/tagger._init_:308: Starting Picard from '/home/zas/src/picard/picard/tagger.py'
DEBUG:/home/zas/src/picard/picard/tagger:Starting Picard from '/home/zas/src/picard/picard/tagger.py'
Different formats comes from different formatters, corresponding code is at https://github.com/metabrainz/picard/blob/e7e80aa1ba6ae2608cafc92de936147d2133ccae/picard/log.py#L139-L176