Así, en nuestro ejemplo, podemos hacer que `tags` sea específicamente una "lista de strings":

{* ../../docs_src/body_nested_models/tutorial002_py310.py hl[12] *}

## Tipos de conjunto { #set-types }

Pero luego pensamos en ello, y nos damos cuenta de que los tags no deberían repetirse, probablemente serían strings únicos.

Y Python tiene un tipo de datos especial para conjuntos de elementos únicos, el `set`.

| `license_info` | `dict` | 對外公開的 API 授權資訊。可包含多個欄位。<details><summary><code>license_info</code> 欄位</summary><table><thead><tr><th>參數</th><th>型別</th><th>說明</th></tr></thead><tbody><tr><td><code>name</code></td><td><code>str</code></td><td><strong>必填</strong>（若有設定 <code>license_info</code>）。API 使用的授權名稱。</td></tr><tr><td><code>identifier</code></td><td><code>str</code></td><td>API 的 [SPDX](https://spdx.org/licenses/) 授權表示式。<code>identifier</code> 欄位與 <code>url</code> 欄位互斥。<small>自 OpenAPI 3.1.0、FastAPI...

   *
   * @since 11.0
   */
  public static final class InvalidCacheLoadException extends RuntimeException {
    public InvalidCacheLoadException(String message) {
      super(message);
    }
  }

   * #entrySet}. If you override {@link #entrySet}, you may wish to override {@link #toString} to
   * forward to this implementation.
   *
   * @since 7.0
   */
  protected String standardToString() {
    return Maps.toStringImpl(this);
  }

            int exp = size();
            int actual = getLength();
            if (exp != actual) {
                throw new IllegalStateException(String.format("Wrong size calculation have %d expect %d", exp, actual));
            }

            return calculatedLength;
        }

        private void setLength(int length) {
            try {

Das bedeutet, dass **jeder Wert**, der in Python von einer Umgebungsvariablen gelesen wird, **ein `str` sein wird**, und jede Konvertierung in einen anderen Typ oder jede Validierung muss im Code vorgenommen werden.

      <span style="background-color:#007166"><font color="#D3D7CF"> app </font></span>  Using import string: <font color="#3465A4">main:app</font>

   <span style="background-color:#007166"><font color="#D3D7CF"> server </font></span>  Server started at <font color="#729FCF"><u style="text-decoration-style:solid">http://0.0.0.0:8000</u></font>

      <span style="background-color:#007166"><font color="#D3D7CF"> app </font></span>  Using import string: <font color="#3465A4">main:app</font>

      <span style="background-color:#007166"><font color="#D3D7CF"> app </font></span>  Using import string: <font color="#3465A4">main:app</font>

   <span style="background-color:#007166"><font color="#D3D7CF"> server </font></span>  Server started at <font color="#729FCF"><u style="text-decoration-style:solid">http://0.0.0.0:8000</u></font>

FastAPI, her *path operation* için bir **unique ID** kullanır. Bu ID, **operation ID** için ve ayrıca request/response'lar için gerekebilecek özel model isimleri için de kullanılır.

Bu fonksiyonu özelleştirebilirsiniz. Bir `APIRoute` alır ve string döndürür.

Örneğin burada ilk tag'i (muhtemelen tek tag'iniz olur) ve *path operation* adını (function adı) kullanıyor.