function address4

def a(x, y):

print("I am from function a")

return x(y)

def b(z):

# z() run the function outside def b(z) on line 13

print("I am from function b")

def d():

print("I am from inner function d")

z() #run the function on line 13

def c(): #register the address of function c with the content below. Function c is not run until function c is called outside on line 9.

print("I am from function c")

return c, d #return only 1 value out as a tuple (c, d)

def d():

print("I am from function d")

a(b,d)[1]() #(c, d)[1]()

a(b,d)[0]() #(c, d)[0]()