POST item to Model
        ---
        post:
          requestBody:
            description: Model schema
            required: true
            content:
              application/json:
                schema:
                  $ref: '#/components/schemas/{{self.__class__.__name__}}.post'
          responses:
            201:
              description: Item inserted
              content:
                application/json:
                  schema:
                    type: object
                    properties:
                      id:
                        type: string
                      result:
                        $ref: '#/components/schemas/{{self.__class__.__name__}}.post'
            400:
              $ref: '#/components/responses/400'
            401:
              $ref: '#/components/responses/401'
            422:
              $ref: '#/components/responses/422'
            500:
              $ref: '#/components/responses/500'

def post(self):
        """POST item to Model
        ---
        post:
          requestBody:
            description: Model schema
            required: true
            content:
              application/json:
                schema:
                  $ref: '#/components/schemas/{{self.__class__.__name__}}.post'
          responses:
            201:
              description: Item inserted
              content:
                application/json:
                  schema:
                    type: object
                    properties:
                      id:
                        type: string
                      result:
                        $ref: '#/components/schemas/{{self.__class__.__name__}}.post'
            400:
              $ref: '#/components/responses/400'
            401:
              $ref: '#/components/responses/401'
            422:
              $ref: '#/components/responses/422'
            500:
              $ref: '#/components/responses/500'
        """
        if not request.is_json:
            return self.response_400(message="Request is not JSON")
        try:
            item = self.add_model_schema.load(request.json)
        except ValidationError as err:
            return self.response_422(message=err.messages)
        # This validates custom Schema with custom validations
        if isinstance(item.data, dict):
            return self.response_422(message=item.errors)
        self.pre_add(item.data)
        try:
            self.datamodel.add(item.data, raise_exception=True)
            self.post_add(item.data)
            return self.response(
                201,
                **{
                    API_RESULT_RES_KEY: self.add_model_schema.dump(
                        item.data, many=False
                    ).data,
                    "id": self.datamodel.get_pk_value(item.data),
                }
            )
        except IntegrityError as e:
            return self.response_422(message=str(e.orig))