input: from typing import List
  
  def generate_password() -> str:
      """ Generate a random password of length 8, which consists of alphanumeric characters and at least one special character.
      >>> generate_password()
      'A2b#c7d9'
      >>> generate_password()
      '4Fg@5HjK'
      """
      import string
      import random
      
      chars = string.ascii_letters + string.digits + string.punctuation
      pwd_length = 8
  
      password = ''
      for i in range(pwd_length):
          password += random.choice(chars)
      
      # Check if at least one special character exists in the password
      if any([char in string.punctuation for char in password]):
          return password
      else:
          return generate_password()
output:     import string
      import random
      
      chars = string.ascii_letters + string.digits + string.punctuation
      pwd_length = 8
  
      password = ''
      for i in range(pwd_length):
          password += random.choice(chars)
      
      # Check if at least one special character exists in the password
      if any([char in string.punctuation for char in password]):
          return password
      else:
          return generate_password()