input: import numpy as np
  
  def runningTotal(arr):
      """ Returns the array with the running total of numbers in the given list.
      >>> runningTotal([1, 2, 3, 4, 5])
      array([ 1,  3,  6, 10, 15])
      >>> runningTotal([10, -5, 3, 0, 7])
      array([10,  5,  8,  8, 15])
      """
      return np.cumsum(arr)
output:     return np.cumsum(arr)