B031 flagged on non-itertools groupby

Recent B031 addition: https://github.com/PyCQA/flake8-bugbear/pull/347

A code that defines a groupby function (not itertools.groupby) will still raise B031 error.

Example:

def groupby(x, y):
    return dict().items()


for _, v in groupby(None, None):
    if v:
        ...
    if v:
        ...

Then:

$ flake8 example.py
example.py:8:8: B031 Using the generator returned from `itertools.groupby()` more than once will do nothing on the second usage. Save the result to a list, if the result is needed multiple times.

flake8: 6.0.0, flake8-bugbear: 23.2.13

Perhaps we can have a better inspection so the error is not raised in such cases?

Reproduce the supplied example with flake8 and flake8-bugbear, then locate the B031 implementation and its existing tests. Compare the handling of a locally defined groupby with itertools.groupby; done means the local function no longer produces B031 while the intended itertools.groupby warning remains covered by tests.