Global variable from multiple file in python [duplicate]

I have searched a lot in different forums including Using global variables between files in Python? and couldn't find any proper answer for my question though there are some topics discussing about global variable and multiple files. I created three dummy codes to explain my question.

globalss.py

test_value = [0]

test.py

from globalss import *
def datagen():
  global test_value
  test_value = [100]
  print('test_value from datagen', test_value)
datagen()
def valchange(x):
  global test_value
  test_value = [x]
  print('test value in val change', test_value)
valchange(1000)

testing.py

from test import *
from globalss import *
print('test_value from testing', test_value)
valchange(22222)
print('test_value from testing', test_value)

testing.py is the file i ran as main.

output

test_value from datagen [100]
test value in val change [1000]
test_value from testing [0]
test value in val change [22222]
test_value from testing [0]

Regardless of operations applied on test_value, testing.py has 0 as its value. So basically from this test codes what i understood is, a module will get the value for a global variable when it is imported. After that whatever happens to that variable from other files, it would not get reflected in that particular module.

All the answers i found from another pages are talking about initializing the variable in a common file and import that file in different modules. As i have shown in the example, that will import the value. but once imported, changes made after that in other files would populate in current file.

My question is, is there a way to share global variables across different file where the values changes will be reflected in all the files.