# python defaults
import sys
def value_generator():
    yield "first_value"
    yield "this will never be returned because I am called once on parse"

values=value_generator()

def foo():
    print("executing foo look at me I am called before runnig main :p")
    return next(values)

    
def fn_with_default(x=foo()):
    print(f"executing fn_with_default which returned {x} from before running main because it was executed when script was parsed :P")

def main():
    print("running main")
    fn_with_default()
    fn_with_default()
    
if __name__ == '__main__':
    main()
# https://python-fiddle.com/saved/iOgOfgILeQWUKJJcF7po