*   <li>Convert between specific preset values using {@link
 *       com.google.common.collect.Maps#asConverter Maps.asConverter}. For example, use this to
 *       create a "fake" converter for a unit test. It is unnecessary (and confusing) to <i>mock</i>
 *       the {@code Converter} type using a mocking framework.
 *   <li>Pass two lambda expressions or method references to the {@link #from from} factory method.

  protected B self() {
    return (B) this;
  }

  // Test Data

  private @Nullable G subjectGenerator;
  // Gets run before every test.
  private Runnable setUp;
  // Gets run at the conclusion of every test.
  private Runnable tearDown;

  @CanIgnoreReturnValue
  protected B usingGenerator(G subjectGenerator) {
    this.subjectGenerator = subjectGenerator;
    return self();
  }

      // timed out. e.g. if we weren't event able to grab the lock within the timeout we would never
      // even check the guard. I don't think we care too much about this use case but it could lead
      // to a confusing error message.
      throw new TimeoutException("Timed out waiting for " + this + " to reach the RUNNING state.");
    }
  }

  @Override
  public final void awaitTerminated() {

The same example would then look like:

{* ../../docs_src/dependencies/tutorial004_an_py310.py hl[19] *}

...and **FastAPI** will know what to do.

/// tip

If that seems more confusing than helpful, disregard it, you don't *need* it.

It is just a shortcut. Because **FastAPI** cares about helping you minimize code repetition.

```console
$ C:\opt\custompython\bin\python
```

</div>

////

Deze informatie is handig wanneer je meer wilt weten over [virtuele omgevingen](virtual-environments.md){.internal-link target=_blank}.

## Conclusion

Hiermee heb je basiskennis van wat **omgevingsvariabelen** zijn en hoe je ze in Python kunt gebruiken.

    if (localInputFuture != null) {
      String message = "inputFuture=[" + localInputFuture + "]";
      if (localTimer != null) {
        long delay = localTimer.getDelay(MILLISECONDS);
        // Negative delays look confusing in an error message
        if (delay > 0) {
          message += ", remaining delay=[" + delay + " ms]";
        }
      }
      return message;
    }
    return null;
  }

  @Override

* rename stop.go file to delete.go to avoid confusion ([#49533](https://github.com/kubernetes/kubernetes/pull/49533), [@dixudx](https://github.com/dixudx))

O mesmo exemplo ficaria então dessa forma:

{* ../../docs_src/dependencies/tutorial004_an_py310.py hl[19] *}

...e o **FastAPI** saberá o que fazer.

/// tip | Dica

Se isso parece mais confuso do que útil, não utilize, você não *precisa* disso.

É apenas um atalho. Por que o **FastAPI** se preocupa em ajudar a minimizar a repetição de código.

El mismo ejemplo se vería entonces así:

{* ../../docs_src/dependencies/tutorial004_an_py310.py hl[19] *}

...y **FastAPI** sabrá qué hacer.

/// tip | Consejo

Si eso parece más confuso que útil, ignóralo, no lo *necesitas*.

Es solo un atajo. Porque a **FastAPI** le importa ayudarte a minimizar la repetición de código.

```console
$ C:\opt\custompython\bin\python
```

</div>

////

Esta información será útil al aprender sobre [Entornos Virtuales](virtual-environments.md){.internal-link target=_blank}.

## Conclusión

Con esto deberías tener una comprensión básica de qué son las **variables de entorno** y cómo usarlas en Python.