input: 
  def printArrayReverse(arr):
      """ Print a python array from the end to the beginning.
      >>> printArrayReverse([1, 2, 3, 4, 5])
      5 4 3 2 1 
      """
  
output:     if not arr:
          return
      printArrayReverse(arr[1:])
      print(arr[0], end=' ')