input: Write a python function to demonstrate optimal use of libraries and efficient data structures by computing the element-wise sum of two lists using NumPy.
  assert elementwise_sum([1, 2, 3], [4, 5, 6])==[5, 7, 9]
  assert elementwise_sum([10, 20, 30], [1, 2, 3])==[11, 22, 33]
  assert elementwise_sum([0, 0, 0], [1, 1, 1])==[1, 1, 1]
output: import numpy as np
  
  def elementwise_sum(list1, list2):
      array1 = np.array(list1)
      array2 = np.array(list2)
      result = array1 + array2
      return result.tolist()