mit 6.0001 recursion - multiplication and factorial implemented via recursion (vs built in '*' or 'math.factorial()')

recursion_fun.py

def mult_rec(x, y):
  if y == 1:
    return x
  else:
    return x + mult_rec(x, y-1) 

def fact_rec(x):
  if x == 1:
    return x
  elif x > 1:
    return x * fact_rec(x-1)
  else:
    print('x must be int >= 1')

if __name__ == "__main__":
  choice = input('(m)ultiplication or (f)actorial?: ').lower()
  if choice == 'm':
    x = int(input('x: '))
    y = int(input('y: '))
    print(mult_rec(x,y))
  elif choice == 'f':
    x = int(input('x: '))
    print(fact_rec(x))