i don't understand how to use a variable outside of a function?

[Rius2]

from this function:

def test(arg)
a = 0
if arg >3:
    a=1
return a

how do i use it in another function?:

def main():
    arg = rand.randrange(0,7)
    test(arg)
    if a = 1:
        print('I don't know what i'm doing')