* **function**: es la función debajo del "decorador" (debajo de `@app.get("/")`).

{* ../../docs_src/first_steps/tutorial001_py39.py hl[7] *}

Esta es una función de Python.

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`:

  This license, the Lesser General Public License, applies to some
specially designated software packages--typically libraries--of the
Free Software Foundation and other authors who decide to use it.  You
can use it too, but we suggest you first think carefully about whether
this license or the ordinary General Public License is the better
strategy to use in any particular case, based on the explanations below.

## Add Labels to PRs

The same GitHub Action <a href="https://github.com/tiangolo/latest-changes" class="external-link" target="_blank">latest-changes</a> uses one label in the PR to decide the section in the release notes to put this PR in.

Make sure you use a supported label from the <a href="https://github.com/tiangolo/latest-changes#using-labels" class="external-link" target="_blank">latest-changes list of labels</a>:

Agora vamos **refatorar** este app um pouco para aumentar a **segurança** e **versatilidade**.

Se você verificar o app anterior, na interface você pode ver que, até agora, ele permite que o cliente decida o `id` do `Hero` a ser criado. 😱

{* ../../docs_src/dependencies/tutorial008e_an_py39.py hl[12,16] *}

`Depends()` recibe un parámetro `scope` que puede ser:

    byte[] buf1 = createBuffer();
    byte[] buf2 = createBuffer();
    while (true) {
      int read1 = read(in1, buf1, 0, BUFFER_SIZE);
      int read2 = read(in2, buf2, 0, BUFFER_SIZE);
      if (read1 != read2 || !arraysEqual(buf1, buf2, read1)) {
        return false;
      } else if (read1 != BUFFER_SIZE) {
        return true;
      }
    }
  }

        percentIndex = i;
        break;
      } else if (Character.digit(c, 16) == -1) {
        return null; // Everything else must be a decimal or hex digit.
      }
    }

    // Now decide which address family to parse.
    if (hasColon) {
      if (hasDot) {
        ipString = convertDottedQuadToHex(ipString);
        if (ipString == null) {
          return null;
        }
      }

   * <p>On the other hand, if for example we are resolving {@code List<A extends B>} to {@code
   * List<A extends String>}, we need to compare that {@code <A extends B>} is unequal to {@code <A
   * extends String>} in order to decide to use the transformed type instead of the original type.
   */
  static final class TypeVariableKey {
    private final TypeVariable<?> var;

    TypeVariableKey(TypeVariable<?> var) {

      while (true) {
        var tryAgain = false
        var readBytesDelivered = -1L
        var errorExceptionToDeliver: IOException? = null

        // 1. Decide what to do in a synchronized block.

        withLock {
          val doReadTimeout = doReadTimeout()
          if (doReadTimeout) {
            readTimeout.enter()
          }
          try {

Now let's **refactor** this app a bit to increase **security** and **versatility**.

If you check the previous app, in the UI you can see that, up to now, it lets the client decide the `id` of the `Hero` to create. 😱

We shouldn't let that happen, they could overwrite an `id` we already have assigned in the DB. Deciding the `id` should be done by the **backend** or the **database**, **not by the client**.