input: 
  def get_even_numbers(start: int, end: int) -> List[int]:
      """Given a range defined by start and end, return a list of all even numbers within that range (inclusive).
      
      >>> get_even_numbers(1, 20)
      [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
      >>> get_even_numbers(5, 10)
      [6, 8, 10]
      >>> get_even_numbers(3, 3)
      []
      """
  
output:     even_numbers = []
      for num in range(start, end + 1):
          if num % 2 == 0:
              even_numbers.append(num)
      return even_numbers