Turning a variable into a class object, via an imported function - class

Question

I have made a class definition...
class Element():
def __init__(self, word_list, type):
self.type = type
self.list = word_list
And on another Python file (practice_page_1) a function definition...
from class_element import Element
test_list = []
def test(word_list):
num = 0
for letter in word_list:
if letter == 'd':
global test_list
test_list = word_list[:num + 1]
test_list = Element(test_list, 'letters')
return True
num += 1
And then on another Python file the operation of the function...
from practice_page_1 import test
from practice_page_1 import test_list
my_list = ['a', 'b', 'c', 'd', 'a', 'a', 'e', 'f', 'a', 'g']
test(my_list)
print(test_list)
When it prints test_list it prints an empty list [] while I was expecting it to print a class object. However if I move the exact same lines of operation back to practice_page_1, it does print test_list as a class object. Why is this?

Answer 1

When you use from ... import ..., the imported object is put in the current namespace. It is a reference to the object itself, not the module variable. If you want to get the most recent changes, use this:
import practice_page_1
my_list = ['a', 'b', 'c', 'd', 'a', 'a', 'e', 'f', 'a', 'g']
practice_page_1.test(my_list)
print(practice_page_1.test_list)
That works because you are now accessing the variable called test in the module namespace instead of the current one (which used to be the same object as that in the module namespace). You probably want to do import ... as ... when you have a module with that long a name, but there you go.