input: from typing import List
  
  def generate_random_string(length: int) -> str:
      """ Generates a random string of the specified length using alphanumeric characters.
      >>> generate_random_string(8)
      'aB3dFg7H'
      >>> generate_random_string(6)
      '1Zx2q4'
      """
output:     import random
      import string
  
      return ''.join(random.choices(string.ascii_letters + string.digits, k=length))