```Python hl_lines="81-83"
    {!> ../../../docs_src/websockets/tutorial003.py!}
    ```

Zum Ausprobieren:

* Öffnen Sie die Anwendung mit mehreren Browser-Tabs.
* Schreiben Sie Nachrichten in den Tabs.
* Schließen Sie dann einen der Tabs.

Das wird die Ausnahme `WebSocketDisconnect` auslösen und alle anderen Clients erhalten eine Nachricht wie:

```
Client #1596980209979 left the chat
```

		if p.HeadingIDs {
			// Parse and remove ID attribute.
			// It must come before trailing '#'s to more closely follow the spec:
			//    The optional closing sequence of #s must be preceded by spaces or tabs
			//    and may be followed by spaces or tabs only.
			// But Goldmark allows it to come after.
			id, s = extractID(p, s)

			// Goldmark is strict about the id syntax.
			for _, c := range id {
				if c >= 0x80 || !isLetterDigit(byte(c)) {

	var tests = []struct {
		markdown, expectedMarkdown string
	}{
		{ // first line is removed
			// Nb. first line is the title of the document, and by removing it you get
			//     more flexibility for include, e.g. include in tabs
			markdown: "line 1\n" +
				"line 2\n" +
				"line 3",
			expectedMarkdown: "line 2\n" +
				"line 3",
		},
		{ // everything after ###SEE ALSO is removed

function openURL(url) {
  chrome.tabs.create({ "url": url })
}

function addLinks() {
  var links = document.getElementsByTagName("a");
  for (var i = 0; i < links.length; i++) {
    var url = links[i].getAttribute("url");
    if (url)
      links[i].addEventListener("click", function () {
        openURL(this.getAttribute("url"));
      });
  }
}

window.addEventListener("load", function () {
  addLinks();

# This test checks that the CC environment variable may contain quotes and
# spaces. Arguments are normally split on spaces, tabs, newlines. If an
# argument contains these characters, the entire argument may be quoted
# with single or double quotes. This is the same as -gcflags and similar
# options.

[short] skip
[!exec:clang] [!exec:gcc] skip
[!cgo] skip

env GOENV=$WORK/go.env
mkdir 'program files'

// license that can be found in the LICENSE file.

package debug_test

import (
	"reflect"
	"runtime/debug"
	"strings"
	"testing"
)

// strip removes two leading tabs after each newline of s.
func strip(s string) string {
	replaced := strings.ReplaceAll(s, "\n\t\t", "\n")
	if len(replaced) > 0 && replaced[0] == '\n' {
		replaced = replaced[1:]
	}
	return replaced
}

=== "Python 3.8+"

    ```Python hl_lines="81-83"
    {!> ../../../docs_src/websockets/tutorial003.py!}
    ```

To try it out:

* Open the app with several browser tabs.
* Write messages from them.
* Then close one of the tabs.

That will raise the `WebSocketDisconnect` exception, and all the other clients will receive a message like:

```
Client #1596980209979 left the chat
```

!!! tip

}

// cleanupForInclude parts of markdown that will make difficult to use it as include in the website:
// - The title of the document (this allow more flexibility for include, e.g. include in tabs)
// - The sections see also, that assumes file will be used as a main page
func cleanupForInclude(md string) string {
	lines := strings.Split(md, "\n")

	cleanMd := ""
	for i, line := range lines {
		if i == 0 {

// removed, if there were any. Otherwise, the input is returned unchanged.
//
// The base64 decoder already skips newline characters, so we don't need to
// filter them out here.
func removeSpacesAndTabs(data []byte) []byte {
	if !bytes.ContainsAny(data, " \t") {
		// Fast path; most base64 data within PEM contains newlines, but
		// no spaces nor tabs. Skip the extra alloc and work.
		return data

	start := i
	for start > 0 && (s[start-1] == ' ' || s[start-1] == '\t') {
		start--
	}
	end := i + 1
	for end < len(s) && (s[end] == ' ' || s[end] == '\t') {
		end++
	}
	// TODO: Do tabs count? That would be a mess.
	if i >= 2 && s[i-1] == ' ' && s[i-2] == ' ' {
		return &HardBreak{}, start, end, true
	}
	return &SoftBreak{}, start, end, true