re.Match.lastgroup is str rather than AnyStr

[jpy-git]

Another tweak to re that I spotted when working through the regex stubs.

re.Match.lastgroup is derived from indexgroup (inverse of groupindex) and therefore must be a str:
https://github.com/python/cpython/blob/0b58bac3e7877d722bdbd3c38913dba2cb212f13/Modules/_sre.c#L2375-L2388

Group names are always stored as strings, even if the pattern and string are bytes:

>>> import re
>>> re.compile(b"(?P<letter>\w)").match(b"a1").lastgroup
'letter'

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉

[AlexWaygood]

Good catch!!