Python. How to get rid of "doubling" of variables?

Question

Python

main.py

import add

b = 2

def main():
    global a
    a = 1
    add.show_test()

main()

add.py

def show_test():
    import main

    print('a', main.a)
    print('b', main.b)

>>>
a 1
b 2
a 1
b 2

Answer 1

Cyclic imports are a sign of great intelligence.
You and the cards in hand)

Answer 2

Are you seriously?
Import is done only in one file, and you import the first into the second, and the second into the first.
Or the first to the second, or the second to the first.

Answer 3

Suggested by smart people. Maybe someone will come in handy ..

import add

b = 2

def main():
    global a
    a = 1
    add.show_test()

if __name__ == '__main__': 
    main()

import __main__ as core

def show_test():
    print('a', core.a)
    print('b', core.b)