* ClassToInstanceMap}</a>.
 *
 * @param <B> the common supertype that all values will share. When in doubt, just use {@link
 *     Object}, or use {@code @Nullable Object} to allow null values.
 * @since 2.0
 */
@DoNotMock("Use ImmutableClassToInstanceMap or MutableClassToInstanceMap")
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface ClassToInstanceMap<B extends @Nullable Object>

linked with the Library has the freedom and the wherewithal to run
that program using a modified version of the Library.

  The precise terms and conditions for copying, distribution and
modification follow.  Pay close attention to the difference between a
"work based on the library" and a "work that uses the library".  The
former contains code derived from the library, whereas the latter must

* Создайте файл `main.py` со следующим содержимым:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

				fmt.Fprintf(h, "part.%d", part.Number)
				fmt.Fprintf(h, "part.%d", part.Size)
			}
			// Previously we checked if we had quorum on DataDir value.
			// We have removed this check to allow reading objects with different DataDir
			// values in a few drives (due to a rebalance-stop race bug)
			// provided their their etags or ModTimes match.

			if !meta.Deleted && meta.Size != 0 {

 * views are modifiable.
 *
 * <p>This class is not threadsafe when any concurrent operations update the multimap. Concurrent
 * read operations will work correctly if the last write <i>happens-before</i> any reads. To allow
 * concurrent update operations, wrap your multimap with a call to {@link
 * Multimaps#synchronizedSetMultimap}.
 *
 * <p><b>Warning:</b> Do not modify either a key <i>or a value</i> of a {@code HashMultimap} in a

	if clientConfig.GetGenericXdsConfigs() != nil {
		configs = clientConfig.GetGenericXdsConfigs()
		return configs
	}

	// FIXME: currently removing the deprecated code below may result in functions not working
	// if there is a mismatch of versions between istiod and istioctl
	// nolint: staticcheck
	for _, config := range clientConfig.GetXdsConfig() {
		var typeURL string

    elementsPlus.add(AFTER_LAST);
    elementsPlus.add(AFTER_LAST_2);
    return Ordering.explicit(Lists.newArrayList(elementsPlus));
  }

  /*
   * All the ContiguousSet generators below manually reject nulls here. In principle, we'd like to
   * defer that to Range, since it's ContiguousSet.create() that's used to create the sets. However,
   * that gets messy here, and we already have null tests for Range.
   */

        }

        int l = args.length;
        Class<?>[] classes = new Class[l];

        for (int i = 0; i < l; ++i) {
            Object arg = args[i];
            // if we are careful down below, a null argument goes in there
            // so we can know that the null was passed to the method
            classes[i] = arg == null ? null : arg.getClass();
        }

          maxSize = 50L * 1024L * 1024L // 50 MiB
      ))
      .build()
```

## EventListener events 

Cache Events are exposed via the EventListener API.  Typical scenarios are below.

### Cache Hit

In the ideal scenario the cache can fulfill the request without any conditional call to the network.
This will skip the normal events such as DNS, connecting to the network, and downloading the response body.

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