Terry J. Reedy added the comment:
Looking at the tempfile code more, I agree with Serhiy that changing it should
be rejected. Python is a duck-typed language (essentially what Martin said).
People should not be over-zealous in using instance checks.
The doc specifically says that Temporary
Serhiy Storchaka added the comment:
I have doubts that making _TemporaryFileWrapper a subclass of IOBase can make
it simpler. It can make it more complex. _TemporaryFileWrapper is a proxy class
with the __getattr__ method which not just return attributes of the underlying
file, but wraps met
Terry J. Reedy added the comment:
TemporaryFile() returns an instance of _TemporaryFileWrapper.
isinstance(TemporaryFile(), io.IOBase) is a sensible thing to do and would be
True if _TemporaryFileWrapper subclassed the appropriate io base file.
The base class for IDLE's stdxxx pseudofiles d
