Cli

def __init__(self, console: Console | None = None) -> None:
    """Create an interactive seam over *console* (defaults to stdio).

    Args:
        console: The console to prompt on; ``StreamConsole`` when omitted.
    """
    self._console: Console = StreamConsole() if console is None else console

async def choose(self, offer: Offer) -> Message:
    """Prompt the person for a message among *offer*'s classes.

    Args:
        offer: What the person may send, and to whom.

    Returns:
        The message the person chose, decoded to its declared class.
    """
    self._console.show(_cli_menu(offer))
    while True:
        chosen, error = await self._attempt_or_error(offer)
        if chosen is not None:
            return chosen
        self._console.show(f'error: {error}')

async def notify(self, subject: Role, envelope: Envelope) -> None:
    """Print *envelope* to the console.

    Args:
        subject: The human's own role.
        envelope: The protocol message being delivered.
    """
    self._console.show(str(envelope))

async def recall(self, subject: Role, envelope: Envelope) -> None:
    """Print a message this person sent in an earlier process.

    Args:
        subject: The human's own role.
        envelope: The protocol message they sent earlier.
    """
    self._console.show(str(envelope))

async def cancel(self, subject: Role, reason: str) -> None:
    """Print that the session ended, and why.

    Args:
        subject: The human's own role.
        reason: Why the session was rolled up.
    """
    self._console.show(f'[{subject.name}] session ended: {reason}')