# libtmux._internal.env.TMUX_PANE

- **Module:** libtmux._internal.env
- **Package:** libtmux
- **Language:** Python
- **Kind:** constant
- **Source:** https://github.com/tmux-python/libtmux/blob/38e368c11117fb4aeb2f082d552cd4f210eae06a/src/libtmux/_internal/env.py#L39
- **Page:** https://libtmux.org/en/py/stable/reference/libtmux-_internal-env-tmux_pane/

```py
libtmux._internal.env.TMUX_PANE: t.Final = "TMUX_PANE"
```

Environment variable tmux exports with the pane's id, e.g. ``%3``.