input: Write a function to find the common elements between two lists and return them in a new list. If there are no common elements, return an empty list. The function should accept two lists as input parameters and return a list containing only the elements that are present in both input lists.
  assert common_elements([1, 2, 3, 4, 8], [2, 6, 8, 10])==[2, 8]
  assert common_elements([3, 5, 7], [2, 6, 8])==[]
  assert common_elements([10, 20, 30], [30, 20, 10])==[10, 20, 30]
  assert common_elements([], [1, 2, 3])==[]
  assert common_elements([1, 2], [])==[]
output: def common_elements(list1, list2):
      return list(set(list1) & set(list2))