input: Write a function to swap the elements of two arrays of integers. Ensure that the two arrays have the same length.
  
  def swap(arr1, arr2):
      assert len(arr1) == len(arr2)
      for i in range(len(arr1)):
          temp = arr1[i]
          arr1[i] = arr2[i]
          arr2[i] = temp
  
  assert swap([3, 5, 6, 9], [2, 4, 7, 8]) == ([2, 4, 7, 8], [3, 5, 6, 9])
  assert swap([1, 2, 3], [4, 5, 6]) == ([4, 5, 6], [1, 2, 3])
  assert swap([], []) == ([], [])
  assert swap([1], [2]) == ([2], [1])
  assert swap([3, 5], [4, 6]) == ([4, 6], [3, 5])
output: def swap(arr1, arr2):
      for i in range(len(arr1)):
          temp = arr1[i]
          arr1[i] = arr2[i]
          arr2[i] = temp