str.count only takes positional args

[sobolevn]

>>> ''.count(x='a')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: str.count() takes no keyword arguments

PyDoc_STRVAR(count__doc__,
             "S.count(sub[, start[, end]]) -> int\n\
\n\
Return the number of non-overlapping occurrences of substring sub in\n\
string S[start:end].  Optional arguments start and end are\n\
interpreted as in slice notation.");

[github-actions]

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