# First Steps { #first-steps }

The simplest FastAPI file could look like this:

{* ../../docs_src/first_steps/tutorial001_py39.py *}

Copy that to a file `main.py`.

Run the live server:

<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 🚀

# Erste Schritte { #first-steps }

Die einfachste FastAPI-Datei könnte wie folgt aussehen:

{* ../../docs_src/first_steps/tutorial001_py39.py *}

Kopieren Sie das in eine Datei `main.py`.

Starten Sie den Live-Server:

<div class="termy">

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

  @SuppressWarnings("GoodTime") // should be a java.time.Duration
  private final long totalLoadTime;

  private final long evictionCount;

  /**
   * Constructs a new {@code CacheStats} instance.
   *
   * <p>Five parameters of the same type in a row is a bad thing, but this class is not constructed
   * by end users and is too fine-grained for a builder.
   */
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration

  @SuppressWarnings("GoodTime") // should be a java.time.Duration
  private final long totalLoadTime;

  private final long evictionCount;

  /**
   * Constructs a new {@code CacheStats} instance.
   *
   * <p>Five parameters of the same type in a row is a bad thing, but this class is not constructed
   * by end users and is too fine-grained for a builder.
   */
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration

### Other (Cleanup or Flake)

     */
    public EntraIdAuthenticator() {
        // Default constructor
    }

    // New configuration keys for Entra ID
    /** Configuration key for Entra ID state time-to-live. */
    protected static final String ENTRAID_STATE_TTL = "entraid.state.ttl";

    /** Configuration key for Entra ID authority URL. */
    protected static final String ENTRAID_AUTHORITY = "entraid.authority";

## Changelog since v1.31.0

## Changes by Kind

### Deprecation

        assertThrows(IllegalStateException.class, () -> closedAuth.getPasswordAsCharArray());
    }

    /**
     * Test authentication TTL (Time To Live)
     */
    @Test
    @DisplayName("Test authentication TTL expiration")
    public void testAuthenticationTTL() throws InterruptedException {

	fmt.Println(bytes.ContainsFunc([]byte("World"), f))
	// Output:
	// false
	// true
}

func ExampleCount() {
	fmt.Println(bytes.Count([]byte("cheese"), []byte("e")))
	fmt.Println(bytes.Count([]byte("five"), []byte(""))) // before & after each rune
	// Output:
	// 3
	// 5
}

func ExampleCut() {
	show := func(s, sep string) {
		before, after, found := bytes.Cut([]byte(s), []byte(sep))

            verify(mockNdrBuffer).advance(8); // sub_authority advance (4 * 2)
            verify(mockNdrBuffer, times(2)).derive(anyInt());

            // Verify identifier_authority bytes (5 zeros + 1 five)
            verify(mockNdrBuffer, times(5)).enc_ndr_small((byte) 0);
            verify(mockNdrBuffer).enc_ndr_small((byte) 5);

            // Verify sub_authority values