input: from typing import List
  
  def runningTotal(arr: List[int]) -> List[int]:
      """ Returns an array with the running total of numbers in a given list using numpy.
      >>> runningTotal([1, 2, 3, 4])
      array([ 1,  3,  6, 10])
      >>> runningTotal([5, 10, 15, 20])
      array([ 5, 15, 30, 50])
      """
      import numpy as np
      return np.cumsum(arr)
output:     import numpy as np
      return np.cumsum(arr)