input: Write a python function to calculate the sum of elements in a list.
  assert calculate_sum([10, 20, 30, 40]) == 100
  assert calculate_sum([1, 2, 3, 4, 5]) == 15
  assert calculate_sum([0, -1, -2, -3, -4]) == -10
output: def calculate_sum(lst):
      return sum(lst)