input: Write a python function to get common items from two lists.
  assert get_common_items([1, 2, 3, 4, 5], [2, 4, 6, 8])==[2, 4]
  assert get_common_items([10, 20, 30, 40, 50], [5, 10, 15, 20])==[10, 20]
  assert get_common_items([7, 8, 9], [10, 11, 12])==[]
output: def get_common_items(list1, list2):
      return list(set(list1) & set(list2))