And you could have a single dependency that requires several other dependencies with `yield`, etc.

You can have any combinations of dependencies that you want.

**FastAPI** will make sure everything is run in the correct order.

/// note | Technical Details

</p>

<p>
Examples of incorrect synchronization are given in the
“Incorrect synchronization” section below.
</p>

<p>
Examples of the limitations on implementations are given in the
“Incorrect compilation” section below.
</p>

<h2 id="synchronization">Synchronization</h2>

<h3 id="init">Initialization</h3>

<p>
Program initialization runs in a single goroutine,

          + (-56.78 - TWO_VALUES_MEAN) * (-789.012 - OTHER_TWO_VALUES_MEAN);

  /**
   * Helper class for testing with non-finite values. {@link #ALL_MANY_VALUES} gives a number of
   * instances with many combinations of finite and non-finite values. All have {@link
   * #MANY_VALUES_COUNT} values. If all the values are finite then the mean is {@link
   * #MANY_VALUES_MEAN} and the sum-of-squares-of-deltas is {@link

### Workerprozesse und Ports { #worker-processes-and-ports }

Erinnern Sie sich aus der Dokumentation [Über HTTPS](https.md), dass nur ein Prozess auf einer Kombination aus Port und IP-Adresse auf einem Server lauschen kann?

Das ist immer noch wahr.

{* ../../docs_src/bigger_applications/app_an_py310/routers/items.py hl[30:31] title["app/routers/items.py"] *}

/// tip | Tipp

Diese letzte Pfadoperation wird eine Kombination von Tags haben: `["items", "custom"]`.

    work need not make them do so.

  A compilation of a covered work with other separate and independent
works, which are not by their nature extensions of the covered work,
and which are not combined with it such as to form a larger program,
in or on a volume of a storage or distribution medium, is called an
"aggregate" if the compilation and its resulting copyright are not

    
    // WRITE_CACHING for directories means:
    // - Can cache file creation/deletion notifications
    // - Can perform optimistic file operations
    
    // Directory-specific combinations
    public static final int DIRECTORY_READ_HANDLE = SMB2_LEASE_READ_CACHING | SMB2_LEASE_HANDLE_CACHING;
    public static final int DIRECTORY_FULL = SMB2_LEASE_FULL;  // All three
}
```

### 3.2 Directory Cache Scopes

    double actualReportedFpp = bf.expectedFpp();
    assertThat(actualReportedFpp).isWithin(0.00033).of(expectedReportedFpp);
  }

  /** Sanity checking with many combinations of false positive rates and expected insertions */
  public void testBasic() {
    for (double fpr = 0.0000001; fpr < 0.1; fpr *= 10) {

Aquí veremos un ejemplo usando [SQLModel](https://sqlmodel.tiangolo.com/).

**SQLModel** está construido sobre [SQLAlchemy](https://www.sqlalchemy.org/) y Pydantic. Fue creado por el mismo autor de **FastAPI** para ser la combinación perfecta para aplicaciones de FastAPI que necesiten usar **bases de datos SQL**.

/// tip | Consejo

{* ../../docs_src/bigger_applications/app_an_py310/routers/items.py hl[30:31] title["app/routers/items.py"] *}

/// tip | Consejo

Esta última path operation tendrá la combinación de tags: `["items", "custom"]`.

Y también tendrá ambas responses en la documentación, una para `404` y otra para `403`.

///

## El `FastAPI` principal { #the-main-fastapi }