it may already exist, even as a closed issue.
-->

<!--
Describe the feature.

Please give us as much context as possible about the feature. For example,
you could include a story about a time when you wanted to use the feature,
and also tell us what you had to do instead. The last part is helpful
because it gives us an idea of how much harder your life is without the
feature.

        That's a lot of work they are doing, but if more FastAPI users came to help others like them just a little bit more, it would be much less effort for them (and you and me 😅).

        By asking questions in a structured way (following this) it will be much easier to help you.

        And there's a high chance that you will find the solution along the way and you won't even have to submit it and wait for an answer. 😎

   */
  public final Optional<@NonNull E> firstMatch(Predicate<? super E> predicate) {
    // Unsafe, but we can't do much about it now.
    return Iterables.<@NonNull E>tryFind((Iterable<@NonNull E>) getDelegate(), predicate);
  }

  /**
   * Returns a fluent iterable that applies {@code function} to each element of this fluent
   * iterable.
   *

   */
  public final Optional<@NonNull E> firstMatch(Predicate<? super E> predicate) {
    // Unsafe, but we can't do much about it now.
    return Iterables.<@NonNull E>tryFind((Iterable<@NonNull E>) getDelegate(), predicate);
  }

  /**
   * Returns a fluent iterable that applies {@code function} to each element of this fluent
   * iterable.
   *

net.ipv4.tcp_timestamps=0

# Increase throughput
net.ipv4.tcp_sack=1

# Low latency mode for TCP
net.ipv4.tcp_low_latency=1

# The following variable is used to tell the kernel how 
# much of the socket buffer space should be used for TCP 
# window size, and how much to save for an application buffer.
net.ipv4.tcp_adv_win_scale=1

# disable RFC2861 behavior
net.ipv4.tcp_slow_start_after_idle = 0

# Fix faulty network setups

again with a little shriek, and went on:  `--that begins with an
M, such as mouse-traps, and the moon, and memory, and muchness--
you know you say things are "much of a muchness"--did you ever
see such a thing as a drawing of a muchness?'

  `Really, now you ask me,' said Alice, very much confused, `I
don't think--'

  `Then you shouldn't talk,' said the Hatter.

again with a little shriek, and went on:  `--that begins with an
M, such as mouse-traps, and the moon, and memory, and muchness--
you know you say things are "much of a muchness"--did you ever
see such a thing as a drawing of a muchness?'

  `Really, now you ask me,' said Alice, very much confused, `I
don't think--'

  `Then you shouldn't talk,' said the Hatter.

You could also create a `JSONResponse` directly and return it.

/// tip

You will normally have much better performance using a [Response Model](../tutorial/response-model.md) than returning a `JSONResponse` directly, as that way it serializes the data using Pydantic, in Rust.

///

## Return a `Response` { #return-a-response }

# Reference

Here's the reference or code API, the classes, functions, parameters, attributes, and
all the FastAPI parts you can use in your applications.

If you want to **learn FastAPI** you are much better off reading the

/**
 * Computes a value, possibly asynchronously. For an example usage and more information, see {@link
 * Futures.FutureCombiner#callAsync(AsyncCallable, java.util.concurrent.Executor)}.
 *
 * <p>Much like {@link java.util.concurrent.Callable}, but returning a {@link ListenableFuture}
 * result.
 *
 * @since 20.0
 */
@GwtCompatible
public interface AsyncCallable<V extends @Nullable Object> {
  /**