input: Write a function to swap the elements of two arrays of integers. The function should ensure that the lengths of both arrays are the same before performing the swap. For each element, swap the corresponding elements between the two arrays.
  
  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]) == None
output: def swap(arr1, arr2):
      if len(arr1) == len(arr2):
          for i in range(len(arr1)):
              temp = arr1[i]
              arr1[i] = arr2[i]
              arr2[i] = temp