Changing a global variable inside a function

Question

I have the following code:

curtains = 0

def bedroom_curtains_open():
    print ("You open your curtains to reveal that it is very dark out.")
    print ("It looks to be about 2am, what woke you?")
    curtains = 1
    bedroom_up()

This, however doesn't change the variable curtains to 1, why is this?

Answer 1

Declare global curtains inside the function.

Then it knows to bind curtains to the global, rather than create a new local in the namespace of the function.