* {@code ByteSink} is not an open, stateful stream that can be written to and closed. Instead, it
 * is an immutable <i>supplier</i> of {@code OutputStream} instances.
 *
 * <p>{@code ByteSink} provides two kinds of methods:
 *
 * <ul>
 *   <li><b>Methods that return a stream:</b> These methods should return a <i>new</i>, independent
 *       instance each time they are called. The caller is responsible for ensuring that the

 * }</pre>
 *
 * <p>Graph algorithms that need additional capabilities (accessing both predecessors and
 * successors, iterating over the edges, etc.) should declare their input to be of a type that
 * provides those capabilities, such as {@link Graph}, {@link ValueGraph}, or {@link Network}.
 *
 * <h3>Additional documentation</h3>
 *
 * <p>See the Guava User Guide for the {@code common.graph} package (<a

			expectedErr: errors.New("MasterKeyID is allowed with aws:kms only"),
			shouldPass:  false,
		},
		// 5. Invalid XML - master key ID not provided when algorithm is set to aws:kms algorithm
		{

	return err.statusCode
}

func (err *s3Error) Error() string {
	return err.message
}

func errMalformedXML(err error) *s3Error {
	return &s3Error{
		code:       "MalformedXML",
		message:    "The XML provided was not well-formed or did not validate against our published schema. Check the service documentation and try again: " + err.Error(),
		statusCode: 400,
		cause:      err,
	}
}

/**
 * Determines a true or false value for a given input; a pre-Java-8 version of {@link
 * java.util.function.Predicate java.util.function.Predicate}.
 *
 * <p>The {@link Predicates} class provides common predicates and related utilities.
 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/FunctionalExplained">the use of {@code Predicate}</a>.
 *
 * <h3>For Java 8+ users</h3>

    @Override
    public void onRemoval(RemovalNotification<K, V> notification) {
      add(notification);
    }
  }

  /**
   * {@link RemovalListener} that counts each {@link RemovalNotification} it receives, and provides
   * access to the most-recently received one.
   */
  static class CountingRemovalListener<K, V> implements RemovalListener<K, V> {
    private final AtomicInteger count = new AtomicInteger();

func (r *PipeReader) CloseWithError(err error) error {
	err = r.PipeReader.CloseWithError(err)
	r.wait()
	return err
}

// WaitPipe implements wait-group backend io.Pipe to provide
// synchronization between read() end with write() end.
func WaitPipe() (*PipeReader, *PipeWriter) {
	r, w := io.Pipe()
	var wg sync.WaitGroup
	wg.Add(1)
	return &PipeReader{
			PipeReader: r,

```Python hl_lines="6-7  21-22"
{!../../docs_src/response_directly/tutorial001.py!}
```

/// note | "Technical Details"

You could also use `from starlette.responses import JSONResponse`.

**FastAPI** provides the same `starlette.responses` as `fastapi.responses` just as a convenience for you, the developer. But most of the available responses come directly from Starlette.

///

## Returning a custom `Response`

///

/// note | "Technical Details"

You could also use `from starlette.requests import Request`.

**FastAPI** provides it as a convenience for you, the developer. But it comes directly from Starlette.

///

### Before and after the `response`

You can add code to be run with the `request`,  before any *path operation* receives it.

* <a href="https://tartiflette.io/" class="external-link" target="_blank">Tartiflette</a>
    * With <a href="https://tartiflette.github.io/tartiflette-asgi/" class="external-link" target="_blank">Tartiflette ASGI</a> to provide ASGI integration
* <a href="https://graphene-python.org/" class="external-link" target="_blank">Graphene</a>