如何在另一个python文件中的方法中使用变量的值？

Question

I have the variable name inside the method control_in(self) which is inside the class Test .

I have tried to make name an attribute by doing:

a) setattr(control_in, name ,"Harry Banes") b) control_in.name = "Harry Banes"

In file b.py I have tried using: a) from a import * b) import a c) from a import Test aa) print(a.Test.control_in.name) ab) print(t1.control_in.name) ac) print(a.t1.control_in.name) ad) global name in every part of the code (I know this is useless but just wanted to mention I tried it.)

I have also tried return name and return control_in.name at the end of the control_in(self) method

and none print the value of the name variable. But everything I put in init method, it does print. Take print(t1.n) for example that prints: numbers .

YES, I've already searched and tried a lot of the solutions other StackOverflow Q&A had and none has worked which is why I am asking personally.

a.py

import b

class Test:
    def __init__(self):
        self.n = "numbers"

    def control_in(self):
        control_in.name = "Harry Banes"

if __name__ == '__main__':
    pass

b.py

from a import *

if __name__ == '__main__':

    t1 = Test()

    print(t1.n) # Successfuly prints "numbers"
    print(t1.control_in.name) # Throws attribute error

I expect the output "Harry Banes" but instead I get this error: AttributeError: 'function' object has no attribute 'name'

I want to use the value from another Class' methods other than init , in another file. Why I want this? Because It's a problem I am having for a way bigger code where I need just 1 variable to make something happen in another function, from another python file but I don't know how to get the variable value.

Answer 1

Firstly, control_in.name = "Harry Banes" is not a valid code because a class method cannot be referred to just by its name, but by its class:

def control_in(self):
    Test.control_in.name = "Harry Banes"

or better yet, use self.__class__ to refer to the class:

def control_in(self):
    self.__class__.control_in.name = "Harry Banes"

Secondly, Test.control_in.name won't be defined until the control_in method is called and executed, so you have to specifically call it:

t1 = Test()
t1.control_in()
print(t1.control_in.name)

This outputs:

Harry Banes

But lastly, there usually isn't any good reason to add attributes to a function object. In this case the Test.control_in.name variable is bound to a class method and is therefore shared across all instances, and should more idiomatically be redefined as a class variable instead:

class Test:
    name = "Harry Banes"

so that you can access name with just Test.name :

print(Test.name)