input: 
  def generate_random_string(length: int) -> str:
      """Generate a random string of the specified length containing alphanumeric characters.
  
      >>> generate_random_string(8)
      'aB3d5FgH'
      >>> generate_random_string(8)
      '12ZxY7kL'
      """
      import string
      import random
  
      chars = string.ascii_letters + string.digits
      return ''.join(random.choice(chars) for _ in range(length))
  
output:     import string
      import random
  
      chars = string.ascii_letters + string.digits
      return ''.join(random.choice(chars) for _ in range(length))