code: def post(self):
          
          resource = self.__model__.query.filter_by(**request.json).first()
          if resource:
              error_message = is_valid_method(self.__model__, resource)
              if error_message:
                  raise BadRequestException(error_message)
              return self._no_content_response()
  
          resource = self.__model__(**request.json)  # pylint: disable=not-callable
          error_message = is_valid_method(self.__model__, resource)
          if error_message:
              raise BadRequestException(error_message)
          db.session().add(resource)
          db.session().commit()
          return self._created_response(resource)
docs: Return the JSON representation of a new resource created through
          an HTTP POST call.
  
          :returns: ``HTTP 201`` if a resource is properly created
          :returns: ``HTTP 204`` if the resource already exists
          :returns: ``HTTP 400`` if the request is malformed or missing data