input: Write a function to interleave elements from two lists.
  assert interleave_lists([1, 2, 3], ['a', 'b', 'c']) == [1, 'a', 2, 'b', 3, 'c']
  assert interleave_lists(['x', 'y', 'z'], [4, 5, 6]) == ['x', 4, 'y', 5, 'z', 6]
  assert interleave_lists([7, 8], ['p', 'q', 'r']) == [7, 'p', 8, 'q']
output: def interleave_lists(list1, list2):
      return [elem for pair in zip(list1, list2) for elem in pair] + list1[len(list2):] + list2[len(list1):]