///

/// info

In this example we use invented custom headers `X-Key` and `X-Token`.

But in real cases, when implementing security, you would get more benefits from using the integrated [Security utilities (the next chapter)](../security/index.md){.internal-link target=_blank}.

///

## Dependencies errors and return values

You can use the same dependency *functions* you use normally.

### Dependency requirements

/// info

If you are using containers, for example with Docker or Kubernetes, I'll tell you more about that in the next chapter: [FastAPI in Containers - Docker](docker.md){.internal-link target=_blank}.

 * acquire(1000)} will result in exactly the same throttling, if any), but it affects the throttling
 * of the <i>next</i> request. I.e., if an expensive task arrives at an idle RateLimiter, it will be
 * granted immediately, but it is the <i>next</i> request that will experience extra throttling,
 * thus paying for the cost of the expensive task.
 *
 * @author Dimitris Andreou
 * @since 13.0
 */

I'll show you some concrete examples in the next chapters.

---

Then the next concepts to consider are all about the program running your actual API (e.g. Uvicorn).

## Program and Process

     */
    void add(Problem.Severity severity, String message, int line, int column, Exception cause);

    /**
     * The next messages will be bound to this source. When calling this method again, previous messages keep
     * their source, but the next messages will use the new source.
     *
     * @param source a source
     */
    void setSource(String source);

    /**
     *

      if (!hasNext()) {
        throw new NoSuchElementException();
      }

      // requireNonNull is safe because of the hasNext check.
      BiEntry<K, V> entry = requireNonNull(next);
      next = entry.nextInKeyInsertionOrder;
      toRemove = entry;
      remaining--;
      return output(entry);
    }

    @Override
    public void remove() {
      if (modCount != expectedModCount) {

				b.RunParallel(func(pb *testing.PB) {
					rng := rand.New(rand.NewSource(time.Now().UnixNano()))
					n := 0
					var latency int64
					managers := grid.Managers
					hosts := grid.Hosts
					for pb.Next() {
						// Pick a random manager.
						src, dst := rng.Intn(len(managers)), rng.Intn(len(managers))
						if src == dst {
							dst = (dst + 1) % len(managers)
						}
						local := managers[src]

    }.test();
  }

  public void testIteratorNoSuchElementException() {
    Iterator<E> iterator = collection.iterator();
    while (iterator.hasNext()) {
      iterator.next();
    }

    assertThrows(NoSuchElementException.class, () -> iterator.next());
  }

    Iterator<Range<C>> itr = rangeSet.asRanges().iterator();
    Range<C> expectedSpan = null;
    if (itr.hasNext()) {
      expectedSpan = itr.next();
      while (itr.hasNext()) {
        expectedSpan = expectedSpan.span(itr.next());
      }
    }

    try {
      Range<C> span = rangeSet.span();
      assertEquals(expectedSpan, span);
    } catch (NoSuchElementException e) {

      StringBuilder sb = new StringBuilder();
      Iterator<String> iterator = components.iterator();
      if (iterator.hasNext()) {
        sb.append(iterator.next().toString());
        while (iterator.hasNext()) {
          sb.append(DELIMITER_STRING);
          sb.append(iterator.next());
        }
      }
      dummy ^= sb.toString().length();
    }
    return dummy;
  }

  /**