return ch - 'a' + 10;
    }
    throw new IllegalArgumentException("Illegal hexadecimal character: " + ch);
  }

  /**
   * Returns {@code true} if {@code object} is a {@link HashCode} instance with the identical byte
   * representation to this hash code.
   *
   * <p><b>Security note:</b> this method uses a constant-time (not short-circuiting) implementation

///

### Paso 2: crea una "instance" de `FastAPI`

{* ../../docs_src/first_steps/tutorial001.py hl[3] *}

Aquí la variable `app` será una "instance" de la clase `FastAPI`.

Este será el punto principal de interacción para crear toda tu API.

### Paso 3: crea una *path operation*

#### Path

////

/// tip | Consejo

Si quieres algo rápido para copiar y pegar, no uses este ejemplo, usa el último más abajo.

///

        return resultBuf.toString();
    }

    /**
     * Sets the query builder for filtering documents.
     *
     * @param queryBuilder the query builder to filter documents
     * @return this UpdateLabelJob instance for method chaining
     */
    public UpdateLabelJob query(final QueryBuilder queryBuilder) {
        this.queryBuilder = queryBuilder;
        return this;
    }

    /** Flag for IDN conversion. */
    protected int flag = 0;

    /** Encoding for URL decoding. */
    protected String encoding = "UTF-8";

    /**
     * Creates a new IdnDnsResolver instance with default settings.
     */
    public IdnDnsResolver() {
        super();
    }

    /**
     * Resolves the given host name to an array of IP addresses.

     * being processed, version 1 is omitted. Value in this property builds
     * <code>org.eclipse.aether.collection.VersionFilter</code> instance.
     *
     * @since 4.0.0
     */
    @Config
    public static final String MAVEN_VERSION_FILTER = "maven.session.versionFilter";

    /**

    }
  }

  /**
   * Remove and return the next event from the recorded sequence.
   *
   * @param eventClass a class to assert that the returned event is an instance of, or null to
   *     take any event class.
   * @param elapsedMs the time in milliseconds elapsed since the immediately-preceding event, or
   *     -1L to take any duration.
   */
  fun takeEvent(

 *
 * It is possible to cancel the finding process by canceling its call.
 *
 * Implementations of this interface are not thread-safe. Each instance is thread-confined to the
 * thread executing the call.
 */
interface RoutePlanner {
  val address: Address

  /** Follow-ups for failed plans and plans that lost a race. */
  val deferredPlans: ArrayDeque<Plan>

    /** Information about the parameterized return type */
    protected final ParameterizedClassDesc parameterizedClassDesc;

    /**
     * Constructs an instance.
     *
     * @param beanDesc
     *            The {@link BeanDesc} of the class that owns this method. Must not be {@literal null}.
     * @param method
     *            The method. Must not be {@literal null}.

Do you want to have an `id` and `email` and not have any `username` in your model? Sure. You can use these same tools.

Do you want to just have a `str`? Or just a `dict`? Or a database class model instance directly? It all works the same way.

You actually don't have users that log in to your application but robots, bots, or other systems, that have just an access token? Again, it all works the same.