input: 
  def generate_even_numbers() -> List[int]:
      """
      Rewrite the given code to generate a list of even numbers between 1 and 20 using list comprehension.
      
      >>> generate_even_numbers()
      [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
      """
  
output:     return [x for x in range(1, 21) if x % 2 == 0]