That same information from the models that is included in OpenAPI is what can be used to **generate the client code**.

### Hey API { #hey-api }

Once we have a FastAPI app with the models, we can use Hey API to generate a TypeScript client. The fastest way to do that is via npx.

```sh
npx @hey-api/openapi-ts -i http://localhost:8000/openapi.json -o src/client
```

  // Features

  private final Set<Feature<?>> features = new LinkedHashSet<>();

  /**
   * Configures this builder to produce tests appropriate for the given features. This method may be
   * called more than once to add features in multiple groups.
   */
  @CanIgnoreReturnValue
  public B withFeatures(Feature<?>... features) {
    return withFeatures(asList(features));
  }

  @CanIgnoreReturnValue

        DirectoryCacheEntry entry = directoryCache.get(directoryPath);
        if (entry == null)
            return;

        // Handle lease break by updating cache behavior
        // Only process if newState is not NONE (0) - a valid lease state
        if (newState != 0) {
            if ((newState & Smb2LeaseState.SMB2_LEASE_READ_CACHING) == 0) {
                // Lost read cache - invalidate directory cache

///

## Subida de Archivos Opcional

Puedes hacer un archivo opcional utilizando anotaciones de tipos estándar y estableciendo un valor por defecto de `None`:

{* ../../docs_src/request_files/tutorial001_02_an_py310.py hl[9,17] *}

## `UploadFile` con Metadatos Adicionales

También puedes usar `File()` con `UploadFile`, por ejemplo, para establecer metadatos adicionales:

Второй аргумент <a href=«https://docs.python.org/3.8/library/os.html#os.getenv» class=«external-link» target=«_blank»>`os.getenv()`</a> - это возвращаемое по умолчанию значение.

Если значение не указано, то по умолчанию оно равно `None`. В данном случае мы указываем `«World»` в качестве значения по умолчанию.
///

Затем можно запустить эту программу на Python:

//// tab | Linux, macOS, Windows Bash

<div class="termy">

```console

                extension = strings[strings.length - 1];
            } else {
                filePrefix = name;
                extension = "";
            }
        } else {
            filePrefix = "none";
            extension = "";
        }
        File inputFile = null;
        File outputFile = null;
        try {
            inputFile =

 * It implements the {@link DocumentReader} interface to provide a way to iterate over documents
 * in a large index without loading all of them into memory at once.
 * </p>
 *
 * <p>
 * The reader supports limiting the number of documents read based on a percentage of the total documents

      return
    }

    val webSocketClient =
      client
        .newBuilder()
        .eventListener(EventListener.NONE)
        .protocols(ONLY_HTTP1)
        .build()
    val request =
      originalRequest
        .newBuilder()
        .header("Upgrade", "websocket")
        .header("Connection", "Upgrade")

// a list of exported functions, and the actual AST, to be rewritten and
// printed.
func (f *File) ParseGo(abspath string, src []byte) {
	// Two different parses: once with comments, once without.
	// The printer is not good enough at printing comments in the
	// right place when we start editing the AST behind its back,
	// so we use ast1 to look for the doc comments on import "C"

    assertFailsWith<IllegalStateException> {
      client.newCall(request).execute()
    }.also { expected ->
      assertThat(expected.message).isEqualTo(
        "network interceptor $interceptor must call proceed() exactly once",
      )
    }
  }

  @Test
  fun networkInterceptorsCannotCallProceedMultipleTimes() {
    server.enqueue(MockResponse())
    server.enqueue(MockResponse())
    val interceptor =