code: def _to_json(self, include_references=True):
          
          if include_references:
              return json.dumps(self._resource._properties, cls=PotionJSONEncoder)
          else:
              return json.dumps(
                  {
                      k: v
                      for k, v in self._resource._properties.items()
                      if not isinstance(v, Resource) and not k.startswith("$")
                  },
                  cls=PotionJSONEncoder,
              )
docs: Convert the model to JSON using the PotionJSONEncode and automatically
          resolving the resource as needed (`_properties` call handles this).