new_contents: from byte import Byte
  
  
  class PBKD:
  
      @staticmethod
      def generate_key(salt=None, message='', iteration_count=1):
          if salt is None:
              salt = PBKD.get_salt()
  
          result = PBKD.HMAC(salt, message)
          for i in range(iteration_count - 1):
              temp = PBKD.HMAC(result, message)
              result = Byte.xor(result, temp)
  
          return result
  
      @staticmethod
      def HMAC(secret, message):
          """
          For hashes using HMAC SHA256 I convert java to python by using this link:
          http://jokecamp.wordpress.com/2012/10/21/examples-of-creating-base64-hashes-using-hmac-sha256-in-different-languages/#python
  
          keySpec = SecretKeySpec(key, "HmacSHA256")#javax.crypto.spec
          mac = Mac.getInstance("HmacSHA256")#javax.crypto.mac
          """
          import hashlib
          import hmac
  
          signature = hmac.new(secret, message, digestmod=hashlib.sha256).digest()
          
          return signature
  
      @staticmethod
      def __get_salt():
          return Byte.hex_to_byte("633f7b241f16d678c20f84e92d9197f1")
  
subject: Create pbkd.py