mymodule.py

def foo() -> int:
    return 42

repro.py

from typing import Protocol

class MyType(Protocol):
    def foo(self) -> int:
        ...


class MyClass:
    def foo(self) -> int:
        return 1

# this is OK
a = MyClass()  # type: MyType

import mymodule
# mymodule.py just contains 
# def foo() -> int:
#     return 42

# but this is not.
b = mymodule  # type: MyType
# mypy complains saying
# Incompatible types in assignment (expression has type Module, variable has type "MyType")


import inspect
print(inspect.signature(a.foo))
print(inspect.signature(b.foo))
# both print: () -> int