// Use reflection to reset the singleton instance between tests
    @BeforeEach
    @AfterEach
    void resetSingleton() {
        try {
            Field instance = SingletonContext.class.getDeclaredField("INSTANCE");
            instance.setAccessible(true);
            instance.set(null, null);
        } catch (NoSuchFieldException | IllegalAccessException e) {

  public void testToString() {
    assertEquals("{}", INSTANCE.toString());
  }

  public void testSize() {
    assertEquals(0, INSTANCE.size());
  }

  public void testGet() {
    assertThat(INSTANCE.get('a', 1)).isNull();
  }

  public void testIsEmpty() {
    assertTrue(INSTANCE.isEmpty());
  }

  public void testCellSet() {
    assertEquals(ImmutableSet.of(), INSTANCE.cellSet());
  }

  public <E extends Comparable<?>> E min(E a, E b) {
    return NaturalOrdering.INSTANCE.max(a, b);
  }

  @Override
  public <E extends Comparable<?>> E min(E a, E b, E c, E... rest) {
    return NaturalOrdering.INSTANCE.max(a, b, c, rest);
  }

  @Override
  public <E extends Comparable<?>> E min(Iterator<E> iterator) {
    return NaturalOrdering.INSTANCE.max(iterator);
  }

  @Override

         * @param status The status to set.
         * @return This ApiResponse instance.
         */
        public ApiResponse status(final Status status) {
            this.status = status.getId();
            return this;
        }

        /**
         * Returns a new ApiResult instance with this ApiResponse.
         * @return A new ApiResult instance.
         */
        public ApiResult result() {

        "/wrapped-class-instance-dependency/",
        "/wrapped-class-instance-async-dependency/",
        "/wrapped-class-instance-gen-dependency/",
        "/wrapped-class-instance-async-gen-dependency/",
        "/class-instance-wrapped-dependency/",
        "/class-instance-wrapped-async-dependency/",
        "/class-instance-async-wrapped-dependency/",
        "/class-instance-async-wrapped-async-dependency/",

But we want to be able to parameterize that fixed content.

## A "callable" instance { #a-callable-instance }

In Python there's a way to make an instance of a class a "callable".

Not the class itself (which is already a callable), but an instance of that class.

To do that, we declare a method `__call__`:

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[12] *}

    instance := grid.NewStream[*Payload, *Req, *Resp](h, newPayload, newReq, newResp)

    // Tweakable options
    instance.WithPayload = true // default true when newPayload != nil
    instance.OutCapacity = 1    // default
    instance.InCapacity = 1     // default true when newReq != nil

    // Register the handler on the manager
    instance.Register(manager, handler, "asubroute")

     * <p>
     * If a root package is specified at instance construction, the specified class name is interpreted as a relative name from the root package.
     * </p>
     *
     * @param className the class name
     * @return <code>true</code> if the class file exists in the resources handled by this instance
     */
    boolean isExistClass(final String className);

## Crear una instance { #create-an-instance }

Podríamos crear una instance de esta clase con:

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[18] *}

Y de esa manera podemos "parametrizar" nuestra dependencia, que ahora tiene `"bar"` dentro de ella, como el atributo `checker.fixed_content`.

## Usar la instance como una dependencia { #use-the-instance-as-a-dependency }

      for (Invokable<?, ?> factory : getFactoriesToTest()) {
        Object instance = instantiate(factory);
        if (instance != null
            && packagesToTest.contains(Reflection.getPackageName(instance.getClass()))) {
          try {
            nullPointerTester.testAllPublicInstanceMethods(instance);
          } catch (AssertionError e) {