"""In Python, you can have multiple variables with the same name. Think
of them as identical twins: their names look the same, but they are in
fact two separate variables that can each contain their own value."""

# This `spam` is a global variable. It was assigned outside of
# all functions:
spam = 'global'

def func1():
    # This `spam` is a local variable because it was assigned inside
    # this function:
    spam = 'local'
    print(spam)

def func2(spam):
    # This `spam` is a local variable. All parameters are local:
    print(spam)

def func3():
    # This `spam` is the global variable, since no `spam` was assigned
    # in this function:
    print(spam)

def func4():
    # This causes an error. `spam` was assigned in this function, making
    # it local, but the variable was used before it was assigned:
    print(spam) # THIS IS NOT THE GLOBAL `spam`.
    spam = 'local' # This assignment makes `spam` in this function local.

    # In this case, think of it as Python checking all the code in the
    # function first before running it to see which variables are
    # global and which are local.

def func5():
    # It doesn't matter where the assignment is. If any assignment
    # statement exists in the function, the variable is local.
    # The code in this `if` block never runs, but that doesn't matter.
    # The `spam` variable here is still local.
    if False:
        spam = 'local' # This assignment makes `spam` in this function local.
    print(spam) # This causes an error since local `spam` wasn't defined.

def func6():
    # This `spam` is global, even though it's assigned in this function,
    # because of the global statement:
    global spam
    print(spam)
    # This assigment doesn't make `spam` local because of the
    # global statement:
    spam = 'global'