input: Write a python function to zip two lists together.
  assert list(zip_two_lists([1, 2, 3], ['a', 'b', 'c']))==[(1, 'a'), (2, 'b'), (3, 'c')]
  assert list(zip_two_lists([4, 5], [6, 7]))==[(4, 6), (5, 7)]
  assert list(zip_two_lists([], []))==[]
output: def zip_two_lists(list1, list2):
      return list(zip(list1, list2))