input: from typing import List
  
  
  def add_numbers(numbers: List[int]) -> int:
      """ Adds all the numbers in a given list together and returns the result.
      >>> add_numbers([1, 2, 3])
      6
      >>> add_numbers([5, 7, 9])
      21
      """
output:     total = 0
      for num in numbers:
          total += num
      return total