}
      return null;
    }
  }

  private static final class InCompletionOrderState<T extends @Nullable Object> {
    // A happens-before edge between the writes of these fields and their reads exists, because
    // in order to read these fields, the corresponding write to incompleteOutputCount must have
    // been read.
    private boolean wasCancelled = false;
    private boolean shouldInterrupt = true;

all types in that type set must be maps, and they must all have identical key types.
</p>

<p>
If the map <code>m</code> is <code>nil</code> or the element <code>m[k]</code>
does not exist, <code>delete</code> is a no-op.
</p>


<h3 id="Length_and_capacity">Length and capacity</h3>

<p>
The built-in functions <code>len</code> and <code>cap</code> take arguments

Estos tipos que tienen tipos internos se denominan tipos "**genéricos**". Y es posible declararlos, incluso con sus tipos internos.

Para declarar esos tipos y los tipos internos, puedes usar el módulo estándar de Python `typing`. Existe específicamente para soportar estas anotaciones de tipos.

#### Versiones más recientes de Python

     * @return number of keys in memory
     */
    public int getKeyCount() {
        return sessionKeys.size();
    }

    /**
     * Check if a session key exists
     *
     * @param sessionId session identifier
     * @return true if key exists
     */
    public boolean hasSessionKey(String sessionId) {
        checkNotClosed();

        } finally {
            if (systemMonitorTask != null) {
                systemMonitorTask.cancel();
            }
            destroyContainer();
        }

        System.exit(exitCode);
    }

    private static void destroyContainer() {
        TimeoutManager.getInstance().stop();
        synchronized (SingletonLaContainerFactory.class) {

        }

        return abbreviateSite(url);
    }

    /**
     * Puts data into the result data map, handling value appending if configured.
     * If data appending is enabled and the key already exists, values are combined into arrays.
     *
     * @param dataMap the data map to modify
     * @param key the key to store the value under
     * @param value the value to store
     */

    checkNotNull(valueComparator);
    return Comparator.<Optional<T>, @Nullable T>comparing(
        o -> orElseNull(o), Comparator.nullsLast(valueComparator));
  }

  // For discussion of why this exists, see the Android flavor.
  private static <T> @Nullable T orElseNull(Optional<T> optional) {
    return optional.orElse(null);
  }

  /**

        // File system errors
        FILE_NOT_FOUND("File not found", ErrorCategory.FILE_SYSTEM, false), PATH_NOT_FOUND("Path not found", ErrorCategory.FILE_SYSTEM,
                false), FILE_EXISTS("File already exists", ErrorCategory.FILE_SYSTEM, false), DIRECTORY_NOT_EMPTY("Directory not empty",
                        ErrorCategory.FILE_SYSTEM, false), DISK_FULL("Disk full", ErrorCategory.RESOURCE,

    return mapEntry(key, value);
  }

  @Override
  protected void expectContents(Collection<Entry<K, V>> expected) {
    // TODO: move this to invariant checks once the appropriate hook exists?
    super.expectContents(expected);
    for (Entry<K, V> entry : expected) {
      assertEquals(
          "Wrong value for key " + entry.getKey(), entry.getValue(), getMap().get(entry.getKey()));
    }
  }

        });

        // Verify hash was reset
        Method resetMethod = findMethod(transport.getClass(), "resetPreauthHash");
        if (resetMethod != null) {
            // Verify the reset method exists
            assertNotNull(resetMethod);
        }
    }

    /**
     * Test that getPreauthIntegrityHash returns a defensive copy
     */
    @Test