Question

I have two files, one of the test.py is

import new.py

class Test:

    def __init__(self):
        return
    def run(self):
        return 1

if __name__ == "__main__":
    one=Test()
    one.run()

and new.py

class New:
    def __init__(self):
        one.run()

New()

Now when i run python test.py I get this error,

Traceback (most recent call last):
  File "test.py", line 1, in <module>
    import new.py
  File "/home/phanindra/Desktop/new.py", line 5, in <module>
    New()
  File "/home/phanindra/Desktop/new.py", line 3, in __init__
    one.run()
NameError: global name 'one' is not defined

But I want to use this instance of one in my New!!
Can I do this??

edit:

I want to access the variable in test.py in new.py to do some process and give them back to test.py. Isn’t this possible?

Answer 1

If you want your New class to use the instance of Test you created, you have to pass it in as part of the constructor.

new.py

class New:
    def __init__(self, one):
        one.run()

test.py

import new

class Test:
    def __init__(self):
        return
    def run(self):
        return 1


if __name__ == "__main__":
    one=Test()
    two = new.New(one);

Playing around with globals is a great way to break your code without realizing how you did it. It is better to explicitly pass in the reference you want to use.