## Overriding dependencies during testing { #overriding-dependencies-during-testing }

There are some scenarios where you might want to override a dependency during testing.

You don't want the original dependency to run (nor any of the sub-dependencies it might have).

Para hacer eso, declaramos un método `__call__`:

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

En este caso, este `__call__` es lo que **FastAPI** usará para comprobar parámetros adicionales y sub-dependencias, y es lo que llamará para pasar un valor al parámetro en tu *path operation function* más adelante.

## Parametrizar la instance

### Sub-dependencies { #sub-dependencies }

 * that selects a particular version and downloads the artifact into the local repository.
 * The {@link org.apache.maven.api.DownloadedArtifact} sub-interface is used when
 * an artifact has been resolved and the {@link org.apache.maven.api.ProducedArtifact} sub-interface when
 * an artifact is being produced by a project.</p>
 *
 * <p>{@link org.apache.maven.api.DependencyCoordinates} instances represent a dependency element in a POM.

}

// forwardTo moves time to t, clearing entries between last update and t.
func (l *lastDayTierStats) forwardTo(t time.Time) {
	if t.IsZero() {
		t = time.Now()
	}

	since := t.Sub(l.UpdatedAt).Hours()
	// within the hour since l.UpdatedAt
	if since < 1 {
		return
	}

	idx, lastIdx := t.Hour(), l.UpdatedAt.Hour()

	l.UpdatedAt = t // update to the latest time index

	if since >= 24 {

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

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

In this case, this `__call__` is what **FastAPI** will use to check for additional parameters and sub-dependencies, and this is what will be called to pass a value to the parameter in your *path operation function* later.

## Parameterize the instance { #parameterize-the-instance }

    //    a*b.example.com, a.*.example.com are not permitted.
    // 2. Asterisk (*) cannot match across domain name labels.
    //    For example, *.example.com matches test.example.com but does not match
    //    sub.test.example.com.
    // 3. Wildcard patterns for single-label domain names are not permitted.

    if (!pattern.startsWith("*.") || pattern.indexOf('*', 1) != -1) {

    checkNotNull(string);
    int end = string.length();
    int index = nextEscapeIndex(string, 0, end);
    return index == end ? string : escapeSlow(string, index);
  }

  /**
   * Scans a sub-sequence of characters from a given {@link CharSequence}, returning the index of
   * the next character that requires escaping.
   *
   * <p><b>Note:</b> When implementing an escaper, it is a good idea to override this method for

For example, if you are squeezing performance, you can install and use <a href="https://github.com/ijl/orjson" class="external-link" target="_blank">`orjson`</a> and set the response to be `ORJSONResponse`.

Import the `Response` class (sub-class) you want to use and declare it in the *path operation decorator*.

For large responses, returning a `Response` directly is much faster than returning a dictionary.

    checkNotNull(string);
    int end = string.length();
    int index = nextEscapeIndex(string, 0, end);
    return index == end ? string : escapeSlow(string, index);
  }

  /**
   * Scans a sub-sequence of characters from a given {@link CharSequence}, returning the index of
   * the next character that requires escaping.
   *
   * <p><b>Note:</b> When implementing an escaper, it is a good idea to override this method for