For example, it was clear that ideally it should be based on standard Python type hints.

Also, the best approach was to use already existing standards.

So, before even starting to code **FastAPI**, I spent several months studying the specs for OpenAPI, JSON Schema, OAuth2, etc. Understanding their relationship, overlap, and differences.

## Design { #design }

Um eines der Beispiele auszuführen, kopieren Sie den Code in eine Datei `main.py` und starten Sie `fastapi dev` mit:

<div class="termy">

```console
$ <font color="#4E9A06">fastapi</font> dev <u style="text-decoration-style:solid">main.py</u>

  <span style="background-color:#009485"><font color="#D3D7CF"> FastAPI </font></span>  Starting development server 🚀

             Searching for package file structure from directories

    val cleaner = get(root)
    assertFailsWith<SSLPeerUnverifiedException> {
      cleaner.clean(certificates, "hostname")
    }
  }

  /** Returns a chain starting at the leaf certificate and progressing to the root.  */
  private fun chainOfLength(length: Int): List<HeldCertificate> {
    val result = mutableListOf<HeldCertificate>()
    for (i in 1..length) {
      result.add(

<div class="termy">

```console
$ <font color="#4E9A06">fastapi</font> dev <u style="text-decoration-style:solid">main.py</u>

  <span style="background-color:#009485"><font color="#D3D7CF"> FastAPI </font></span>  Starting development server 🚀

             Searching for package file structure from directories with
             <font color="#3465A4">__init__.py</font> files

<div class="termy">

```console
$ <font color="#4E9A06">fastapi</font> dev <u style="text-decoration-style:solid">main.py</u>

  <span style="background-color:#009485"><font color="#D3D7CF"> FastAPI </font></span>  Starting development server 🚀

             Searching for package file structure from directories with
             <font color="#3465A4">__init__.py</font> files

 *       <i>j</i><sup>th</sup> item in the <i>i</i><sup>th</sup> equality group, where both equality
 *       groups and the items within equality groups are numbered starting from 1. When either a
 *       constructor argument or an equal object is provided, that becomes group 1.
 * </ul>
 *
 * @author Jim McMaster
 * @author Jige Yu
 * @since 10.0
 */
@GwtCompatible
@NullMarked

<div class="termy">

```console
$ <font color="#4E9A06">fastapi</font> dev <u style="text-decoration-style:solid">main.py</u>

  <span style="background-color:#009485"><font color="#D3D7CF"> FastAPI </font></span>  Starting development server 🚀

             Searching for package file structure from directories with
             <font color="#3465A4">__init__.py</font> files

<div class="termy">

```console
$ <font color="#4E9A06">fastapi</font> dev <u style="text-decoration-style:solid">main.py</u>

  <span style="background-color:#009485"><font color="#D3D7CF"> FastAPI </font></span>  Starting development server 🚀

             Searching for package file structure from directories
             with <font color="#3465A4">__init__.py</font> files

   *
   * <p>The default implementation returns a new {@link Executor} that sets the name of its threads
   * to the string returned by {@link #serviceName}
   */
  protected Executor executor() {
    return command -> newThread(serviceName(), command).start();
  }

  @Override
  public String toString() {
    return serviceName() + " [" + state() + "]";
  }

  @Override
  public final boolean isRunning() {

	NoDelay     bool             // Indicates callers to enable TCP_NODELAY on the net.Conn
	Interface   string           // This is a VRF device passed via `--interface` flag
	Trace       func(msg string) // Trace when starting.
	IdleTimeout time.Duration    // Incoming TCP read/write timeout
}

// ForWebsocket returns TCPOptions valid for websocket net.Conn