Multiple targets could match in write function of io.BytesIO subclass

For example:

import io

class Test(io.BytesIO): pass

x = Test()
x.write(b"")

results in a

Multiple targets could match: write(object), write(IBufferProtocol)

I'm guessing it's because the object overload is an override of a virtual? @BCSharp any idea?

Comes from test_gzip (see https://github.com/IronLanguages/ironpython3/pull/1071).

Also affects truncate and readinto (and probably other io type/method combinations):

import io

class Test(io.BytesIO): pass

x = Test()
x.truncate(0)
x.readinto(bytearray())

Start with the Python reproducer for the io.BytesIO subclass and compare it with test_gzip and the linked pull request. Trace overload resolution for write, truncate, and readinto, then verify that these calls no longer report multiple matching targets while preserving the relevant overload behavior.