input: 
  def generate_password():
      """Generate a random password of length 8, which consists of alphanumeric characters and at least one special character.
      >>> generated_password = generate_password()
      >>> len(generated_password) == 8 and any(char in string.punctuation for char in generated_password)
      True
      """
      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)
      
      if any(char in string.punctuation for char in password):
          return password
      else:
          return generate_password()
  
  print(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)
      
      if any(char in string.punctuation for char in password):
          return password
      else:
          return generate_password()