code: def _encrypt_password(self, password):
          
          if self.encryption_mode.lower() == 'crypt':
              return self._crypt_password(password)
          elif self.encryption_mode.lower() == 'md5':
              return self._md5_password(password)
          elif self.encryption_mode.lower() == 'md5-base':
              return self._md5_base_password(password)
          else:
              raise UnknownEncryptionMode(self.encryption_mode)
docs: encrypt the password for given mode