input: 
  from typing import List
  import string
  import random
  
  def generate_random_string(length: int) -> str:
      """Generates a random string of the given length containing 
      alphanumeric characters.
      
      >>> generate_random_string(8) 
      'aB3d5F7g'
      >>> generate_random_string(8)
      '1Z2x3C4v'
      """
      chars = string.ascii_letters + string.digits
      return ''.join(random.choice(chars) for _ in range(length))
  
output:     chars = string.ascii_letters + string.digits
      return ''.join(random.choice(chars) for _ in range(length))