I use this command and change every usage of BS (case in point https://gerrit.wikimedia.org/r/#/c/83372/4/reflinks.py) grep "(?:from|import) BeautifulSoup" ~/compat-git/*.py you can do it and see
As I said on my last reply there could be other scripts from bot owners which use bs directly and not via wikipedia/pywikibot module. I suggest waiting for additional opinions before merging to the repo.
Greetings xqt
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