Class<Unsafe> k = Unsafe.class;
                for (Field f : k.getDeclaredFields()) {
                  f.setAccessible(true);
                  Object x = f.get(null);
                  if (k.isInstance(x)) return k.cast(x);
                }
                throw new NoSuchFieldError("the Unsafe");
              }
            });
      } catch (PrivilegedActionException e) {

    }

    @Override
    public final void run() {
      try {
        realRun();
        threadShouldThrow(exceptionClass.getSimpleName());
      } catch (Throwable t) {
        if (!exceptionClass.isInstance(t)) threadUnexpectedException(t);
      }
    }
  }

  public abstract class ThreadShouldThrow extends Thread {
    protected abstract void realRun() throws Throwable;

    final Class<?> exceptionClass;

        when {
          isOptional && value == optionalValue -> {
            // Write nothing.
          }

          else -> {
            for ((type, adapter) in choices) {
              if (type.isInstance(value) || (value == null && type == Unit::class)) {
                (adapter as DerAdapter<Any?>).toDer(writer, value)
                return
              }
            }
          }
        }
      }

              Class<Unsafe> k = Unsafe.class;
              for (Field f : k.getDeclaredFields()) {
                f.setAccessible(true);
                Object x = f.get(null);
                if (k.isInstance(x)) return k.cast(x);
              }
              throw new NoSuchFieldError("the Unsafe");
            }
          });
    } catch (PrivilegedActionException e) {

    }

    @Override
    public final void run() {
      try {
        realRun();
        threadShouldThrow(exceptionClass.getSimpleName());
      } catch (Throwable t) {
        if (!exceptionClass.isInstance(t)) threadUnexpectedException(t);
      }
    }
  }

  public abstract class ThreadShouldThrow extends Thread {
    protected abstract void realRun() throws Throwable;

    final Class<?> exceptionClass;

    private void persistResumptionData(MavenExecutionResult result, MavenSession session) {
        boolean hasLifecycleExecutionExceptions =
                result.getExceptions().stream().anyMatch(LifecycleExecutionException.class::isInstance);

        if (hasLifecycleExecutionExceptions) {
            MavenProject rootProject = session.getAllProjects().stream()
                    .filter(MavenProject::isExecutionRoot)
                    .findFirst()

   * desiredType}.
   */
  @SuppressWarnings("unchecked") // can cast to <T> because non-Ts are removed
  @GwtIncompatible // Class.isInstance
  public static <T> UnmodifiableIterator<T> filter(Iterator<?> unfiltered, Class<T> desiredType) {
    return (UnmodifiableIterator<T>) filter(unfiltered, instanceOf(desiredType));
  }

  /**

*   `tf.compat.v1.Session`

	<component name="crawler" class="org.codelibs.fess.crawler.Crawler" instance="prototype" >
	</component>

	<!-- Crawler Thread -->
	<component name="crawlerThread" class="org.codelibs.fess.crawler.CrawlerThread" instance="prototype" >
	</component>

	<!-- Entity -->
	<component name="accessResult" class="org.codelibs.fess.crawler.entity.AccessResultImpl" instance="prototype" >
	</component>

## Parameterize the instance

And now, we can use `__init__` to declare the parameters of the instance that we can use to "parameterize" the dependency:

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[9] *}

In this case, **FastAPI** won't ever touch or care about `__init__`, we will use it directly in our code.

## Create an instance

We could create an instance of this class with: