---

If you just don't know, use normal `def`.

---

**Note**: You can mix `def` and `async def` in your *path operation functions* as much as you need and define each one using the best option for you. FastAPI will do the right thing with them.

Anyway, in any of the cases above, FastAPI will still work asynchronously and be extremely fast.

//// tab | Python 3.8+

```Python hl_lines="31  37"
{!> ../../docs_src/response_model/tutorial006.py!}
```

////

## Recap

Use the *path operation decorator's* parameter `response_model` to define response models and especially to ensure private data is filtered out.

  if (op_reg_data->shape_inference_fn == nullptr) {
    status->status =
        InvalidArgument("No shape inference function exists for op '",
                        node_def.op(), "', did you forget to define it?");
    return;
  }

  status->status = c.Run(op_reg_data->shape_inference_fn);
  if (!status->status.ok()) return;

  // Set output_shapes.
  TF_ShapeAndTypeList* output_shapes_result =

special prefixes means that there is no way to directly reference a C
identifier that starts with "struct_", "union_", "enum_", or
"sizeof_", such as a function named "struct_function".
A workaround is to use a "#define" in the preamble, as in
"#define c_struct_function struct_function" and then in the
Go code refer to "C.c_struct_function".

A C function may be declared in the Go file with a parameter type of

  * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
  */

                .build());
        options.addOption(Option.builder(Character.toString(SET_USER_PROPERTY))
                .numberOfArgs(2)
                .valueSeparator('=')
                .desc("Define a user property")
                .build());
        options.addOption(Option.builder(Character.toString(OFFLINE))
                .longOpt("offline")
                .desc("Work offline")
                .build());

     *
     * That combination upsets NullPointerTester, which wants any call that passes null for a
     * non-@Nullable parameter to trigger a NullPointerException.
     *
     * (We still define this empty method to keep PackageSanityTests from generating its own
     * automated nullness tests, which would fail.)
     */
  }

  private static final Object IGNORE_ME =
      new Object() {

	wg.Wait()
}

// newMinioResourceCollector describes the collector
// and returns reference of minio resource Collector
// It creates the Prometheus Description which is used
// to define Metric and  help string
func newMinioResourceCollector(metricsGroups []*MetricsGroupV2) *minioResourceCollector {
	return &minioResourceCollector{
		metricsGroups: metricsGroups,

## Classe de resposta padrão

Quando você criar uma instância da classe **FastAPI** ou um `APIRouter` você pode especificar qual classe de resposta utilizar por padrão.

O padrão que define isso é o `default_response_class`.

No exemplo abaixo, o **FastAPI** irá utilizar `ORJSONResponse` por padrão, em todas as *operações de rota*, em vez de `JSONResponse`.

```Python hl_lines="2  4"

n a||s?n+(Ws(e)?"roky":"let"):n+"lety"}}function Es(e,a,t,s){var n={m:["eine Minute","einer Minute"],h:["eine Stunde","einer Stunde"],d:["ein Tag","einem Tag"],dd:[e+" Tage",e+" Tagen"],w:["eine Woche","einer Woche"],M:["ein Monat","einem Monat"],MM:[e+" Monate",e+" Monaten"],y:["ein Jahr","einem Jahr"],yy:[e+" Jahre",e+" Jahren"]};return a?n[t][0]:n[t][1]}function Fs(e,a,t,s){var n={m:["eine Minute","einer Minute"],h:["eine Stunde","einer Stunde"],d:["ein Tag","einem Tag"],dd:[e+" Tage",e+" Tagen"],w:["eine...