# Settings and Environment Variables

In many cases your application could need some external settings or configurations, for example secret keys, database credentials, credentials for email services, etc.

Most of these settings are variable (can change), like database URLs. And many could be sensitive, like secrets.

For this reason it's common to provide them in environment variables that are read by the application.

/// tip

        .isEqualTo(
            InetAddresses.getCoercedIPv4Address(
                InetAddresses.forString("2001:0000:5136:f378:9000:73bf:3fff:fdd2")));

    // Test that an address hashes in to the 224.0.0.0/3 number-space.
    int coercedInt =
        InetAddresses.coerceToInteger(
            InetAddresses.getCoercedIPv4Address(InetAddresses.forString("2001:4860::1")));

"Switch" statements provide multi-way execution.
An expression or type is compared to the "cases"
inside the "switch" to determine which branch
to execute.
</p>

<pre class="ebnf">
SwitchStmt = ExprSwitchStmt | TypeSwitchStmt .
</pre>

<p>
There are two forms: expression switches and type switches.
In an expression switch, the cases contain expressions that are compared
against the value of the switch expression.

    int getHash();

    /** Gets the key for this entry. */
    K getKey();

    /** Gets the value for the entry. */
    V getValue();
  }

  /*
   * Note: the following classes have a lot of duplicate code. It sucks, but it saves a lot of
   * memory. If only Java had mixins!
   */

  /** Base class for {@link InternalEntry} implementations for strong keys. */

@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class MapInterfaceTest<K extends @Nullable Object, V extends @Nullable Object>
    extends TestCase {

  /** A key type that is not assignable to any classes but Object. */
  private static final class IncompatibleKeyType {
    @Override
    public String toString() {
      return "IncompatibleKeyType";
    }
  }

  protected final boolean supportsPut;

Vous faites cela avec les types Python standard modernes.

Vous n'avez pas à apprendre une nouvelle syntaxe, les méthodes ou les classes d'une bibliothèque spécifique, etc.

Juste du **Python** standard.

Par exemple, pour un `int`:

```Python
item_id: int
```

ou pour un modèle `Item` plus complexe :

```Python

}

// SetCreatedAt preserves the CreatedAt time for bucket across sites in site replication. It defaults to
// creation time of bucket on this cluster in all other cases.
func (b *BucketMetadata) SetCreatedAt(createdAt time.Time) {
	if b.Created.IsZero() {
		b.Created = UTCNow()
	}
	if !createdAt.IsZero() {
		b.Created = createdAt.UTC()
	}
}

   *
   * The connection is implicit, and will generally relate to the last [connectionAcquired] event.
   *
   * This will usually be invoked only 1 time for a single [Call], exceptions are a limited set of
   * cases including failure recovery.
   *
   * Prior to OkHttp 4.3 this was incorrectly invoked when the client was ready to read the response
   * body. This was misleading for tracing because it was too early.
   */

Mas quando você importa `Query`, `Path`, `Depends`, `Security` entre outros de `fastapi`, eles são na verdade funções que retornam classes especiais.

///

## Utilize `SecurityScopes`

Agora atualize a dependência `get_current_user`.

Este é o usado pelas dependências acima.

  }

  /**
   * We don't have API support for rfc822Name values (email addresses) in the subject alternative
   * name, but we don't crash either.
   */
  @Test
  fun `unsupported general name tag`() {
    val certificateByteString =
      (
        "MIIFEDCCA/igAwIBAgIRAJK4dE9xztDibHKj2NXZJbIwDQYJKoZIhvcNAQELBQA" +