input: 
  import random
  import string
  
  def generate_password():
      """
      Generate a random password consisting of 8 characters including letters, numbers, 
      and special characters.
      >>> generate_password()
      'aB3$7#9z'  # Example output, actual output will vary
      """
      password_characters = string.ascii_letters + string.digits + string.punctuation
      password = ''.join(random.choice(password_characters) for i in range(8))
      return password
  
output:     password_characters = string.ascii_letters + string.digits + string.punctuation
      password = ''.join(random.choice(password_characters) for i in range(8))
      return password