input: from typing import List
  
  def generate_even_numbers(limit: int) -> List[int]:
      """
      Generate a list of even numbers within the given limit using list comprehension.
      
      >>> generate_even_numbers(21)
      [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
      """
output:     return [x for x in range(2, limit + 1, 2)]