input: Write a function to calculate the total sum of all elements of a list. The function should take a list of numbers as input and return their sum. If the list is empty, return 0.
  assert calculate_sum_of_list([1, 2, 3, 4])==10
  assert calculate_sum_of_list([0, 0, 0, 0])==0
  assert calculate_sum_of_list([-1, -2, -3, -4])==-10
  assert calculate_sum_of_list([])==0
output: def calculate_sum_of_list(numbers):
      if not numbers:
          return 0
      return sum(numbers)