input: Write a python function to calculate the sum of all elements in a list.
  assert sumoflist([1, 4, 2, 5, 9]) == 21
  assert sumoflist([10, 20, 30, 40]) == 100
  assert sumoflist([5, 15, 25, 35, 45]) == 125
output: def sumoflist(lst):
      return sum(lst)