input: Write a python function to create a sequence generator that yields numbers from 0 to 7.
  assert list(create_sequence()) == [0, 1, 2, 3, 4, 5, 6, 7]
  assert list(create_sequence()) == [0, 1, 2, 3, 4, 5, 6, 7]
output: def create_sequence():
      for i in range(8):
          yield i