input: Below is an instruction that describes a task. Write a response that appropriately completes the request.
  
  ### Instruction:
  Create a Python function that takes a list of integers and returns the sum of all even numbers in the list.
  
  ### Input:
  
  
  ### Output:
  def sum_of_evens(numbers: List[int]) -> int:
      """
      Takes a list of integers and returns the sum of all even numbers in the list.
      
      >>> sum_of_evens([1, 2, 3, 4, 5, 6])
      12
      >>> sum_of_evens([7, 8, 9, 10])
      18
      
      """
      return sum(num for num in numbers if num % 2 == 0)
output:     return sum(num for num in numbers if num % 2 == 0)