full_name = user_dict["full_name"],
    hashed_password = hashed_password,
)
```

/// warning

The supporting additional functions `fake_password_hasher` and `fake_save_user` are just to demo a possible flow of the data, but they of course are not providing any real security.

///

## Reduce duplication { #reduce-duplication }

Reducing code duplication is one of the core ideas in **FastAPI**.

  /**
   * Returns true if this body expects at most one call to [writeTo] and can be transmitted
   * at most once. This is typically used when writing the request body is destructive and it is not
   * possible to recreate the request body after it has been sent.
   *
   * This method returns false unless it is overridden by a subclass.
   *

    return this;
  }

  /**
   * Returns a new thread factory using the options supplied during the building process. After
   * building, it is still possible to change the options used to build the ThreadFactory and/or
   * build again. State is not shared amongst built instances.
   *
   * <p><b>Java 21+ users:</b> use {@link Thread.Builder#factory()} instead.
   *

You can also use `File()` with `UploadFile`, for example, to set additional metadata:

{* ../../docs_src/request_files/tutorial001_03_an_py310.py hl[9,15] *}

## Multiple File Uploads { #multiple-file-uploads }

It's possible to upload several files at the same time.

They would be associated to the same "form field" sent using "form data".

To use that, declare a list of `bytes` or `UploadFile`:

//     setting will be set to this value. This setting will be only applied to newly created jobs (manual changes with Active Full
//     processing possible from the customer side).
//     Optional value, default 1024, allowed values 256,512,1024,4096,8192, value defined in KB size.
//

{* ../../docs_src/request_files/tutorial001_03_an_py310.py hl[9,15] *}

## Téléverser plusieurs fichiers { #multiple-file-uploads }

Il est possible de téléverser plusieurs fichiers en même temps.

Ils seraient associés au même « champ de formulaire » envoyé en « données de formulaire ».

Pour cela, déclarez une `list` de `bytes` ou d'`UploadFile` :

   * {@inheritDoc}
   *
   * <p>This implementation of {@code getAllPresent} lacks any insight into the internal cache data
   * structure, and is thus forced to return the query keys instead of the cached keys. This is only
   * possible with an unsafe cast which requires {@code keys} to actually be of type {@code K}.
   *
   * @since 11.0
   */
  /*
   * <? extends Object> is mostly the same as <?> to plain Java. But to nullness checkers, they

   *
   * @param file the file to read from
   * @return a byte array containing all the bytes from file
   * @throws IllegalArgumentException if the file is bigger than the largest possible byte array
   *     (2^31 - 1)
   * @throws IOException if an I/O error occurs
   */
  public static byte[] toByteArray(File file) throws IOException {
    return asByteSource(file).read();
  }

  /**

the compiler, e.g. suppressing type-checking, raw generics, and so on. However,
this isn't always possible or practical. In such cases, you should use the
`@SuppressWarnings` annotations to silence the compiler warning, trying to keep
the scope of the suppression as small as possible. Where a piece of code
requires a lot of suppressions, it may be better to apply a single suppression

    .build();
```

Client Authentication
---------------------

The above scenario is representative of most TLS set ups: the client uses certificates to validate
the identity of a server. The converse is also possible. Here we create a server that authenticates
a client and a client that authenticates a server.

```java
// Create the root for client and server to trust. We could also use different roots for each!