### Import `HTTPException` { #import-httpexception }

{* ../../docs_src/handling_errors/tutorial001.py hl[1] *}

### Raise an `HTTPException` in your code { #raise-an-httpexception-in-your-code }

`HTTPException` is a normal Python exception with additional data relevant for APIs.

Because it's a Python exception, you don't `return` it, you `raise` it.

	// data that describes the next file. These meta data "files" should not
	// normally be visible to the outside. As such, this loop iterates through
	// one or more "header files" until it finds a "normal file".
	format := FormatUSTAR | FormatPAX | FormatGNU
	for {
		// Discard the remainder of the file and any padding.
		if err := discard(tr.r, tr.curr.physicalRemaining()); err != nil {
			return nil, err
		}

		"policy":    encodedPolicy,
		"signature": signature,
	}

	maps.Copy(formData, formInputData)

	// Create the multipart form.
	var buf bytes.Buffer
	w := multipart.NewWriter(&buf)

	// Set the normal formData
	for k, v := range formData {
		w.WriteField(k, v)
	}
	// Set the File formData
	writer, err := w.CreateFormFile("file", "upload.txt")
	if err != nil {
		// return nil, err
		return nil, err

{* ../../docs_src/settings/app02_an_py39/main.py hl[6,12:13] *}

/// tip | Consejo

Hablaremos del `@lru_cache` en un momento.

Por ahora puedes asumir que `get_settings()` es una función normal.

///

Y luego podemos requerirlo desde la *path operation function* como una dependencia y usarlo donde lo necesitemos.

{* ../../docs_src/settings/app02_an_py39/main.py hl[17,19:21] *}

   * Lists#newArrayList}.
   */
  public void testArraysAsList() {
    List<String> ourWay = Lists.newArrayList("foo", "bar", "baz");
    List<String> otherWay = asList("foo", "bar", "baz");

    // They're logically equal
    assertEquals(ourWay, otherWay);

    // The result of Arrays.asList() is mutable
    otherWay.set(0, "FOO");
    assertEquals("FOO", otherWay.get(0));

There could be cases where you need to do some **custom validation** that can't be done with the parameters shown above.

In those cases, you can use a **custom validator function** that is applied after the normal validation (e.g. after validating that the value is a `str`).

   * the corresponding argument value from {@code args}; or, if the placeholder and argument counts
   * do not match, returns a best-effort form of that string. Will not throw an exception under
   * normal conditions.
   *
   * <p><b>Note:</b> For most string-formatting needs, use {@link String#format String.format},
   * {@link java.io.PrintWriter#format PrintWriter.format}, and related methods. These support the

Será llamada por **FastAPI** cuando reciba un request en la URL "`/`" usando una operación `GET`.

En este caso, es una función `async`.

---

También podrías definirla como una función normal en lugar de `async def`:

{* ../../docs_src/first_steps/tutorial003.py hl[7] *}

/// note | Nota

This package does not support disk spanning.

A note about ZIP64:

To be backwards compatible the FileHeader has both 32 and 64 bit Size
fields. The 64 bit fields will always contain the correct value and
for normal archives both fields will be the same. For files requiring
the ZIP64 format the 32 bit fields will be 0xffffffff and the 64 bit
fields must be used instead.

[ZIP specification]: https://support.pkware.com/pkzip/appnote
*/

        assertEquals(testString, result);
    }

    @ParameterizedTest
    @DisplayName("Test readDataWireFormat with various share types")
    @CsvSource({ "0, SHARE, Normal share", "1, PRINTER, Printer share", "3, IPC$, IPC share", "32768, HIDDEN, Hidden share", // 0x8000 - hidden flag in lower 16 bits
            "32769, HIDDENP, Hidden printer" // 0x8001 - hidden flag + printer type
    })