* Returns the identity function.
   *
   * <p><b>Discouraged:</b> Prefer using a lambda like {@code v -> v}, which is shorter and often
   * more readable.
   */
  // implementation is "fully variant"; E has become a "pass-through" type
  @SuppressWarnings("unchecked")
  public static <E extends @Nullable Object> Function<E, E> identity() {
    return (Function<E, E>) IdentityFunction.INSTANCE;
  }

  // enum singleton pattern

  private enum SupplierFunctionImpl implements SupplierFunction<@Nullable Object> {
    INSTANCE;

    // Note: This makes T a "pass-through type"
    @Override
    public @Nullable Object apply(Supplier<@Nullable Object> input) {
      return input.get();
    }

    @Override
    public String toString() {

---

„_Ich bin überglücklich mit **FastAPI**. Es macht so viel Spaß!_“

      for (TwoArg.Action second : TwoArg.Action.values()) {
        TwoArg bar = new TwoArg(first, second);
        if (first.equals(TwoArg.Action.THROW_A_NPE)) {
          verifyBarPass(method, bar); // only pass if 1st param throws NPE
        } else {
          verifyBarFail(method, bar);
        }
      }
    }
  }

  public void testTwoArgNullableNormal() throws Exception {

- `(*"k8s.io/client-go/rest".Request).{Do,DoRaw,Stream,Watch}` now require callers to pass a `context.Context` as an argument. The context is used for timeout and cancellation signaling and to pass supplementary information to round trippers in the wrapped transport chain. If you don't need any of this functionality, it is sufficient to pass a context created with `context.Background()` to these functions. The `(*"k8s.io/client-go/rest".Request).Context` method...

   * long} values are boxed into {@link Long} instances on demand, which can be very expensive. The
   * returned list should be used once and discarded. For any usages beyond that, pass the returned
   * list to {@link com.google.common.collect.ImmutableList#copyOf(Collection) ImmutableList.copyOf}
   * and use that list instead.
   */
  public List<Long> asList() {
    /*

   * int} values are boxed into {@link Integer} instances on demand, which can be very expensive.
   * The returned list should be used once and discarded. For any usages beyond that, pass the
   * returned list to {@link com.google.common.collect.ImmutableList#copyOf(Collection)
   * ImmutableList.copyOf} and use that list instead.
   */
  public List<Integer> asList() {
    /*

  private enum SupplierFunctionImpl implements SupplierFunction<@Nullable Object> {
    INSTANCE;

    // Note: This makes T a "pass-through type"
    @Override
    public @Nullable Object apply(Supplier<@Nullable Object> input) {
      return input.get();
    }

    @Override
    public String toString() {

       * all inputs for exceptions *if* we're collecting values. If we're not, then the listener
       * doesn't need access to the futures again, so we can just pass `null`.
       *
       * TODO(b/112550045): Allocating a single, cheaper listener is (I think) only an optimization.
       * If we make some other optimizations, this one will no longer be necessary. The optimization

## Context Managers { #context-managers }

### What are "Context Managers" { #what-are-context-managers }