input: Write a function that uses numpy to return an array with the running total of numbers in a given list. The function should take a list as input and return a list with cumulative sums.
  
  ### Function:
  
  import numpy as np
  
  def runningTotal(arr):
      return np.cumsum(arr)
  
  
  ### Test Cases:
  
  assert list(runningTotal([1, 2, 3, 4])) == [1, 3, 6, 10]
  assert list(runningTotal([2, 2, -2, 2])) == [2, 4, 2, 4]
  assert list(runningTotal([0, 0, 0, 0])) == [0, 0, 0, 0]
  assert list(runningTotal([10])) == [10]
  assert list(runningTotal([])) == []
  
output: import numpy as np
  
  def runningTotal(arr):
      return np.cumsum(arr)