this.list = list;
    }

    /**
     * Captures an object to be closed when a {@link ClosingFuture} pipeline is done.
     *
     * <p>For users of the {@code -jre} flavor of Guava, the object can be any {@code
     * AutoCloseable}. For users of the {@code -android} flavor, the object must be a {@code
     * Closeable}. (For more about the flavors, see <a