*
   * <p>Note that a successful call to this method could cause the size of the bimap to increase by
   * one, stay the same, or even decrease by one.
   *
   * <p><b>Warning:</b> If an existing entry with this value is removed, the key for that entry is
   * discarded and not returned.
   *
   * @param key the key with which the specified value is to be associated

但是你也希望它能够接受新的条目。并且当这些条目不存在时，会自动创建并返回 201 「创建」的 HTTP 状态码。

要实现它，导入 `JSONResponse`，然后在其中直接返回你的内容，并将 `status_code` 设置为为你要的值。

{* ../../docs_src/additional_status_codes/tutorial001.py hl[4,25] *}

/// warning | 警告

当你直接返回一个像上面例子中的 `Response` 对象时，它会直接返回。

FastAPI 不会用模型等对该响应进行序列化。

确保其中有你想要的数据，且返回的值为合法的 JSON（如果你使用 `JSONResponse` 的话）。

///

/// note | 技术细节

   * @throws ArithmeticException if {@code mode} is {@link RoundingMode#UNNECESSARY} and {@code x}
   *     is not a power of two
   */
  @SuppressWarnings("fallthrough")
  // TODO(kevinb): remove after this warning is disabled globally
  public static int log2(BigInteger x, RoundingMode mode) {
    checkPositive("x", checkNotNull(x));
    int logFloor = x.bitLength() - 1;
    switch (mode) {
      case UNNECESSARY:

Die Datei- und Formularfelder werden als Formulardaten hochgeladen, und Sie erhalten diese Dateien und Formularfelder.

Und Sie können einige der Dateien als `bytes` und einige als `UploadFile` deklarieren.

/// warning | Achtung

 * Subclasses should override one or more methods to modify the behavior of the backing deque as
 * desired per the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingBlockingDeque} forward <b>indiscriminately</b>
 * to the methods of the delegate. For example, overriding {@link #add} alone <b>will not</b> change

👀 [📨 📨 🔗](response-directly.md){.internal-link target=_blank}, 👆 💪 🔐 📨 🔗 👆 *➡ 🛠️*, 🛬 ⚫️.

🎏 🖼 ⚪️➡️ 🔛, 🛬 `HTMLResponse`, 💪 👀 💖:

{* ../../docs_src/custom_response/tutorial003.py hl[2,7,19] *}

/// warning

`Response` 📨 🔗 👆 *➡ 🛠️ 🔢* 🏆 🚫 📄 🗄 (🖼, `Content-Type` 🏆 🚫 📄) & 🏆 🚫 ⭐ 🏧 🎓 🩺.

///

/// info

↗️, ☑ `Content-Type` 🎚, 👔 📟, ♒️, 🔜 👟 ⚪️➡️ `Response` 🎚 👆 📨.

///

If for some reason you need to disable automatic conversion of underscores to hyphens, set the parameter `convert_underscores` of `Header` to `False`:

{* ../../docs_src/header_params/tutorial002_an_py310.py hl[10] *}

/// warning

Before setting `convert_underscores` to `False`, bear in mind that some HTTP proxies and servers disallow the usage of headers with underscores.

///

## Duplicate headers { #duplicate-headers }

///

/// warning | Aviso

     */
    @Nonnull
    Settings getEffectiveSettings();

    /**
     * Gets the problems that were encountered during the settings building. Note that only problems of severity
     * {@link BuilderProblem.Severity#WARNING} and below are reported here. Problems with a higher severity level cause
     * the settings builder to fail with a {@link SettingsBuilderException}.
     *

    @Nonnull
    PersistedToolchains getEffectiveToolchains();

    /**
     * Gets the problems that were encountered during the settings building. Note that only problems of severity
     * {@link BuilderProblem.Severity#WARNING} and below are reported here. Problems with a higher severity level cause
     * the settings builder to fail with a {@link ToolchainsBuilderException}.
     *