testEmptyRangeSubMultiset(
        sortedMultiset.subMultiset(a.getElement(), OPEN, a.getElement(), OPEN));
    testEmptyRangeSubMultiset(
        sortedMultiset.subMultiset(a.getElement(), OPEN, a.getElement(), CLOSED));
    testEmptyRangeSubMultiset(
        sortedMultiset.subMultiset(b.getElement(), CLOSED, a.getElement(), CLOSED));
    testEmptyRangeSubMultiset(

With that you can connect the WebSocket and then send and receive messages:

<img src="/img/tutorial/websockets/image05.png">

## Handling disconnections and multiple clients

When a WebSocket connection is closed, the `await websocket.receive_text()` will raise a `WebSocketDisconnect` exception, which you can then catch and handle like in this example.

//// tab | Python 3.9+

```Python hl_lines="79-81"

@SuppressSignatureCheck
sealed class CallEvent {
  abstract val timestampNs: Long
  abstract val call: Call

  val name: String
    get() = javaClass.simpleName

  /** Returns if the event closes this event, or null if this is no open event. */
  open fun closes(event: CallEvent): Boolean? = null

  data class ProxySelectStart(
    override val timestampNs: Long,
    override val call: Call,
    val url: HttpUrl,
  ) : CallEvent()

   * characters can be read, the remaining characters are returned and the stream is closed.
   */
  private fun readAscii(
    inputStream: InputStream,
    count: Int,
  ): String {
    val result = StringBuilder()
    for (i in 0 until count) {
      val value = inputStream.read()
      if (value == -1) {
        inputStream.close()
        break
      }
      result.append(value.toChar())
    }

                    log.debug("Failed to close session", e);
                }
                finally {
                    iter.remove();
                }
            }

            if ( this.socket != null ) {
                this.socket.shutdownOutput();
                this.out.close();
                this.in.close();
                this.socket.close();
                log.trace("Socket closed");

// and it is flake-prone to check for closure after calling it, this retries for a bit to make
// sure the netns is closed eventually.
func assertNSClosed(t *testing.T, closed *atomic.Bool) {
	for i := 0; i < 5; i++ {
		if closed.Load() {
			return
		}
		time.Sleep(1 * time.Second)
	}
	t.Fatal("NS not closed")

   * (inclusive) to {@code upper} (inclusive). (These are the same values contained in {@code
   * Range.closed(lower, upper)}.)
   *
   * @throws IllegalArgumentException if {@code lower} is greater than {@code upper}
   * @since 23.0
   */
  public static ContiguousSet<Integer> closed(int lower, int upper) {
    return create(Range.closed(lower, upper), DiscreteDomain.integers());
  }

   * response body is empty this is invoked immediately before returning that to the application.
   *
   * If the application closes the response body before attempting a read, this is invoked at the
   * time it is closed.
   *
   * The connection is implicit, and will generally relate to the last [connectionAcquired] event.
   *

	file := os.Stdin
	if filename != "-" {
		var err error
		file, err = os.Open(filename)
		if err != nil {
			return nil, err
		}
	}
	defer func() {
		if err := file.Close(); err != nil {
			log.Errorf("failed to close %s: %s", filename, err)
		}
	}()
	return io.ReadAll(file)
}

func extractZtunnelConfigDump(kubeClient kube.CLIClient, podName, podNamespace string) ([]byte, error) {

			xioutil.SafeClose(c.done)
			c.done = nil
		}
	}
	return n, err
}

func (c *closeNotifier) Close() error {
	if c.done != nil {
		xioutil.SafeClose(c.done)
		c.done = nil
	}
	return c.rc.Close()
}

// keepHTTPReqResponseAlive can be used to avoid timeouts with long storage
// operations, such as bitrot verification or data usage scanning.
// Every 10 seconds a space character is sent.