//// tab | Python 3.9+

```Python hl_lines="79-81"
{!> ../../docs_src/websockets/tutorial003_py39.py!}
```

////

//// tab | Python 3.8+

```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.

.nav-tabs.flex-column .nav-link:hover {\n  background-color: #3f474e;\n}\n\n.dark-mode .nav-tabs.flex-column.nav-tabs-right {\n  border-color: #56606a;\n}\n\n.dark-mode .nav-tabs.flex-column.nav-tabs-right .nav-link.active, .dark-mode .nav-tabs.flex-column.nav-tabs-right .nav-link:focus, .dark-mode .nav-tabs.flex-column.nav-tabs-right .nav-link:hover {\n  border-color: #56606a #56606a #56606a transparent;\n}\n\n.dark-mode .navbar-light {\n  background-color: #f8f9fa;\n}\n\n.dark-mode .navbar-dark...

  - content.code.copy
  # - content.code.select
  - content.footnote.tooltips
  - content.tabs.link
  - content.tooltips
  - navigation.footer
  - navigation.indexes
  - navigation.instant
  - navigation.instant.prefetch
  # - navigation.instant.preview
  - navigation.instant.progress
  - navigation.path
  - navigation.tabs
  - navigation.tabs.sticky
  - navigation.top
  - navigation.tracking
  - search.highlight

#dee2e6}.nav-tabs.flex-column.nav-tabs-right{border-left:1px solid #dee2e6;border-right:0}.nav-tabs.flex-column.nav-tabs-right .nav-link{border-bottom-left-radius:0;border-bottom-right-radius:.25rem;border-top-left-radius:0;border-top-right-radius:.25rem;margin-left:-1px}.nav-tabs.flex-column.nav-tabs-right .nav-link:focus,.nav-tabs.flex-column.nav-tabs-right .nav-link:hover{border-color:#e9ecef #e9ecef #e9ecef transparent}.nav-tabs.flex-column.nav-tabs-right .nav-item.show .nav-link,.nav-tabs.flex-column.nav-tabs-right...

//// tab | Python 3.9+

```Python hl_lines="79-81"
{!> ../../docs_src/websockets/tutorial003_py39.py!}
```

////

//// tab | 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.

    "UP",  # pyupgrade
]
ignore = [
    "E501",  # line too long, handled by black
    "B008",  # do not perform function calls in argument defaults
    "C901",  # too complex
    "W191",  # indentation contains tabs
]

[tool.ruff.lint.per-file-ignores]
"__init__.py" = ["F401"]
"docs_src/dependencies/tutorial007.py" = ["F821"]
"docs_src/dependencies/tutorial008.py" = ["F821"]
"docs_src/dependencies/tutorial009.py" = ["F821"]

    * You can normally quickly detect it by going to the "Files changed" tab in the PR and checking if the updated file(s) starts with `docs/en/docs`. The original version of the docs is always in English, so in `docs/en/docs`.
* `lang-all`: Translations

text-decoration:none}.nav-link.disabled{color:#6c757d;pointer-events:none;cursor:default}.nav-tabs{border-bottom:1px solid #dee2e6}.nav-tabs .nav-link{margin-bottom:-1px;background-color:transparent;border:1px solid transparent;border-top-left-radius:.25rem;border-top-right-radius:.25rem}.nav-tabs .nav-link:focus,.nav-tabs .nav-link:hover{isolation:isolate;border-color:#e9ecef #e9ecef #dee2e6}.nav-tabs .nav-link.disabled{color:#6c757d;background-color:transparent;border-color:transparent}.nav-tabs...

pointer-events: none;\n    cursor: default;\n  }\n}\n\n//\n// Tabs\n//\n\n.nav-tabs {\n  border-bottom: $nav-tabs-border-width solid $nav-tabs-border-color;\n\n  .nav-link {\n    margin-bottom: -$nav-tabs-border-width;\n    background-color: transparent;\n    border: $nav-tabs-border-width solid transparent;\n    @include border-top-radius($nav-tabs-border-radius);\n\n    @include hover-focus() {\n      // Prevents active .nav-link tab overlapping focus outline of previous/next .nav-link\n      isolation:...

            Doc(
                """
                A list of tags used by OpenAPI, these are the same `tags` you can set
                in the *path operations*, like:

                * `@app.get("/users/", tags=["users"])`
                * `@app.get("/items/", tags=["items"])`

                The order of the tags can be used to specify the order shown in