input: from typing import List
  
  
  def generate_random_password(letters: List[str], numbers: List[str], characters: List[str]) -> str:
      """
      Generate a random password using a combination of given letters, numbers, and characters.
      
      >>> generate_random_password(['a', 'b', 'c'], ['1', '2', '3'], ['!', '@', '#'])
      random generated password with 8 characters
      >>> generate_random_password(['A', 'B', 'C'], ['4', '5', '6'], ['$', '%', '^'])
      random generated password with 8 characters
      """
output:     import random
      all_chars = letters + numbers + characters
      password = ''.join(random.choice(all_chars) for _ in range(8))
      return password