Why won’t it return the variable?

I want to return x and y from the functions but when I put in return x or y, it still says it is undefined. Could someone help me figure out where I’m going wrong?

import time
usernames = 'Codswollop'
passwords = 'Fishcake420'

def password():
  x = input('Please enter your password: ')
  if len(x) < 8:
    print('Password not long enough. Please try again. ')
    password()
  else:
    print('Thank you!')
    return x

def username():
  y = input('Please enter your username: ')
  contains_digit = False #starts as false
  for i in list(y): #repeats the amount of times there are characters in the username.
    if i.isdigit(): #if i, the iteration (each character), is a digit:
      contains_digit = True #set to true because a digit was detected
  if contains_digit == True: #if a digit was detected then:
    print('Contains digit. Please try again. ')
    time.sleep(1)
    username() #restarts function, asking for username again
  else:
    return y


username()
password()

if y == usernames:
  if x == passwords:
    print('access granted')