code: def update(self, item, encrypt=True, **kwargs):
          
          response = self._new_response()
          if self._check_supported_op('update', response):
              if self._prototype_handler.check(item, 'update', response):
                  if encrypt:
                      self._encrypt(item)
                  params = {'Item': item}
                  self._call_ddb_method(self.table.put_item,
                                        params, response)
                  if response.status == 'success':
                      response.data = item
          response.prepare()
          return response
docs: Updates the item based on the current values of the dictionary passed
          in.