TDD Fibonaci numbers

fib.py

def memoize(func):
  cache = {}
  def wrapper(n):
    if not n in cache:
      cache[n] = func(n)
    return cache[n]
  return wrapper

@memoize
def fib(num):
  if num == 0:
    return 0
  if num <= 2:
    return 1
  else:
    return fib(num - 1) + fib(num - 2)

def fib_loop(num):
  x = 0
  y = 1
  result = 0
  if(num == 1):
    return 1
  i = 1
  while (i < num):
    result = x + y
    x = y
    y = result
    i = i + 1
  return result    

def test_fib0():
  assert fib(0) == 0

def test_fib1():
  assert fib(1) == 1

def test_fib2():
  assert fib(2) == 1

def test_fib3():
  assert fib(3) == 2

def test_fib4():
  assert fib(4) == 3

def test_fib12():
  assert fib(12) == 144

def test_fib15():
  assert fib(15) == 610

def test_fib40():
  assert fib(40) == 102334155