* {@code SetMultimap} instead, two presidents would have vanished, and last names might or might
 * not appear in chronological order.
 *
 * <p><b>Warning:</b> instances of type {@code Multimap} may not implement {@link Object#equals} in
 * the way you expect. Multimaps containing the same key-value pairs, even in the same order, may or
 * may not be equal and may or may not have the same {@code hashCode}. The recommended subinterfaces

   * this method returns {@code true} if {@code iterator1} and {@code iterator2} contain the same
   * number of elements and every element of {@code iterator1} is equal to the corresponding element
   * of {@code iterator2}.
   *
   * <p>Note that this will modify the supplied iterators, since they will have been advanced some
   * number of elements forward.

   * this method returns {@code true} if {@code iterator1} and {@code iterator2} contain the same
   * number of elements and every element of {@code iterator1} is equal to the corresponding element
   * of {@code iterator2}.
   *
   * <p>Note that this will modify the supplied iterators, since they will have been advanced some
   * number of elements forward.

And then in our code, we parse that YAML content directly, and then we are again using the same Pydantic model to validate the YAML content:

{* ../../docs_src/path_operation_advanced_configuration/tutorial007_py310.py hl[24:31] *}

/// tip

Here we reuse the same Pydantic model.

But the same way, we could have validated it in some other way.

   * Ascii.truncate("foobar", 5, "..."); // returns "fo..."
   * }
   *
   * <p><b>Note:</b> This method <i>may</i> work with certain non-ASCII text but is not safe for use
   * with arbitrary Unicode text. It is mostly intended for use with text that is known to be safe
   * for use with it (such as all-ASCII text) and for simple debugging text. When using this method,
   * consider the following:
   *
   * <ul>

---> 100%
```

</div>

////

//// tab | `uv`

If you have [`uv`](https://github.com/astral-sh/uv):

<div class="termy">

```console
$ uv pip install "fastapi[standard]"
---> 100%
```

</div>

////

### Install from `requirements.txt` { #install-from-requirements-txt }

If you have a `requirements.txt`, you can now use it to install its packages.

//// tab | `pip`

    private Builder() {}

    /**
     * Sets the safe range of characters for the escaper. Characters in this range that have no
     * explicit replacement are considered 'safe' and remain unescaped in the output. If {@code
     * safeMax < safeMin} then the safe range is empty.
     *
     * @param safeMin the lowest 'safe' character
     * @param safeMax the highest 'safe' character
     * @return the builder instance
     */

  /**
   * Returns an immutable list of the values for the given key. If no mappings in the multimap have
   * the provided key, an empty immutable list is returned. The values are in the same order as the
   * parameters used to build this multimap.
   */
  @Override
  public ImmutableList<V> get(K key) {
    // This cast is safe as its type is known in constructor.
    ImmutableList<V> list = (ImmutableList<V>) map.get(key);

In this example, to be able to have both `HTTPException`s in the same code, Starlette's exceptions is renamed to `StarletteHTTPException`:

```Python
from starlette.exceptions import HTTPException as StarletteHTTPException
```

### Reuse **FastAPI**'s exception handlers { #reuse-fastapis-exception-handlers }

In your production system, you probably have a frontend created with a modern framework like React, Vue.js or Angular.

And to communicate using WebSockets with your backend you would probably use your frontend's utilities.

Or you might have a native mobile application that communicates with your WebSocket backend directly, in native code.

Or you might have any other way to communicate with the WebSocket endpoint.

---