Issue with annotation six.byte2int starting 1.16.21.2

[levincarmel]

Hi,
Starting 1.16.21.2 we have an issue with mypy failing for annotations of six.byte2int.
We had this method:

def byte2int(c: Union[bytes, int]) -> int:
    if isinstance(c, bytes):
        return six.byte2int(c)
    return c

which was called the following way:
pp_fingerprint = ":".join("{:02x}".format(byte2int(c)) for c in fingerprint).upper()

This used to work until now, but now we get this failure:
Argument 1 to "byte2int" has incompatible type "bytes"; expected "SupportsGetItem[int, <nothing>]"
Is this an issue with this release? Or are we supposed to fix our annotations in some way?

Thanks in advance!

[AlexWaygood]

Cc. @Avasam

[Avasam]

The example can be simplified to:

import six
six.byte2int(b"1")

Weird mypy-specific issue that I ironically didn't catch because I was specifically trying to not use bytes.
An overload easily fixes this, PR incoming.

Ref python/mypy#14032 because I don't know if it's the same issue we were having with itemgetter.

Update: Seems to be caused by outdated typeshed stub. This can be discussed in the PR below.

[JelleZijlstra]

@levincarmel what version of mypy are you running?