Python: circular imports needed for type checking

Question

First of all: I do know that there are already many questions and answers to the topic of the circular imports.

The answer is more or less: \"Design your Module/Class s

Answer 1

You could just defer the import in bar.py like this:

class Bar(object):

    def __init__(self, arg_instance_of_foo):
        from foo import Foo
        if not isinstance(arg_instance_of_foo, Foo):
            raise TypeError()