{* ../../docs_src/sql_databases/tutorial001_an_py310.py ln[21:22] hl[21:22] *}

### Créer une dépendance de session { #create-a-session-dependency }

Une **`Session`** est ce qui stocke les **objets en mémoire** et suit les modifications nécessaires des données, puis **utilise l'`engine`** pour communiquer avec la base.

labels.sso_type=SSO Type
labels.crawling_user_agent=User Agent
labels.slack_webhook_urls=Slack Webhook URLs
labels.google_chat_webhook_urls=Google Chat Webhook URLs
labels.log_notification_enabled=Log Notification
labels.log_notification_level=Log Notification Level
labels.notification_advance_search=Advanced Search Page
labels.ldap_security_authentication=Security Authentication
labels.ldap_initial_context_factory=Initial Context Factory

Esto hará que FastAPI omita la generación del modelo de response y de esa manera puedes tener cualquier anotación de tipo de retorno que necesites sin que afecte a tu aplicación FastAPI. 🤓

## Parámetros de codificación del Modelo de Response { #response-model-encoding-parameters }

Tu modelo de response podría tener valores por defecto, como:

{* ../../docs_src/response_model/tutorial004_py310.py hl[9,11:12] *}

labels.sso_type=SSO Type
labels.crawling_user_agent=User Agent
labels.slack_webhook_urls=Slack Webhook URLs
labels.google_chat_webhook_urls=Google Chat Webhook URLs
labels.log_notification_enabled=Log Notification
labels.log_notification_level=Log Notification Level
labels.notification_advance_search=Advanced Search Page
labels.ldap_security_authentication=Security Authentication
labels.ldap_initial_context_factory=Initial Context Factory

 * an {@code ArrayTable} concurrently and one of the threads modifies its value, there is no
 * guarantee that the new value will be fully visible to the other threads. To guarantee that
 * modifications are visible, synchronize access to the table. Unlike other {@code Table}
 * implementations, synchronization is unnecessary between a thread that writes to one cell and a
 * thread that reads from another.
 *

   * elements.length) are all {@code null}.
   */
  @VisibleForTesting transient @Nullable Object @Nullable [] elements;

  /**
   * Keeps track of metadata like the number of hash table bits and modifications of this data
   * structure (to make it possible to throw ConcurrentModificationException in the iterator). Note
   * that we choose not to make this volatile, so we do less of a "best effort" to track such

	ErrInvalidSSECustomerParameters
	ErrIncompatibleEncryptionMethod
	ErrKMSNotConfigured
	ErrKMSKeyNotFoundException
	ErrKMSDefaultKeyAlreadyConfigured

	ErrNoAccessKey
	ErrInvalidToken

	// Bucket notification related errors.
	ErrEventNotification
	ErrARNNotification
	ErrRegionNotification
	ErrOverlappingFilterNotification
	ErrFilterNameInvalid
	ErrFilterNamePrefix
	ErrFilterNameSuffix
	ErrFilterValueInvalid

      notifyStarted();
    }

    @Override
    protected void doStop() {
      notifyStopped();
    }
  }

  /*
   * A NoOp service that will delay the startup and shutdown notification for a configurable amount
   * of time.
   */
  private static class NoOpDelayedService extends NoOpService {
    private final long delay;

    NoOpDelayedService(long delay) {
      this.delay = delay;
    }

labels.sso_type=SSO Type
labels.crawling_user_agent=User Agent
labels.slack_webhook_urls=Slack Webhook URLs
labels.google_chat_webhook_urls=Google Chat Webhook URLs
labels.log_notification_enabled=Log Notification
labels.log_notification_level=Log Notification Level
labels.notification_advance_search=Advanced Search Page
labels.ldap_security_authentication=Security Authentication
labels.ldap_initial_context_factory=Initial Context Factory

      notifyStarted();
    }

    @Override
    protected void doStop() {
      notifyStopped();
    }
  }

  /*
   * A NoOp service that will delay the startup and shutdown notification for a configurable amount
   * of time.
   */
  private static class NoOpDelayedService extends NoOpService {
    private final long delay;

    NoOpDelayedService(long delay) {
      this.delay = delay;
    }