[Python] How can I get a --version to the root of a typer.Typer application?

My CLI applications typically have subcommands. I want to have the --version flag at the root of my CLI applications, but with Typer I've only seen ways to put it to a command. I want to add it to the typer.Typer object (the root) itself. How can I do that?

What I've tried


import typer
from typing import Optional

__version__ = "0.1.0"


def version_callback(value: bool):
if value:
typer.echo(f"Awesome CLI Version: {__version__}")
raise typer.Exit()


app = typer.Typer(
add_completion=False,
)


@app.command()
def main(
version: Optional[bool] = typer.Option(
None, "--version", callback=version_callback
),
) -> None:
pass


@app.command()
def foo() -> None:
pass


if __name__ == "__main__":
app()


This gives

$ python cli.py --help
Usage: cli.py [OPTIONS] COMMAND [ARGS]...

Options:
--help Show this message and exit.

Commands:
foo
main

$ python cli.py main --help
Usage: cli.py main [OPTIONS]

Options:
--version
--help Show this message and exit.


What I wanted:

$ python cli.py --help
Usage: cli.py [OPTIONS] COMMAND [ARGS]...

Options:
--version
--help Show this message and exit.

Commands:
foo

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