startup.py 文件源码

def require_command(
    runner: Runner, command: str, message: Optional[str] = None
):
    if message is None:
        message = "Please install " + command
    try:
        runner.get_output(["which", command])
    except CalledProcessError as e:
        sys.stderr.write(message + "\n")
        sys.stderr.write(
            '(Ran "which {}" to check in your $PATH.)\n'.format(command)
        )
        sys.stderr.write(
            "See the documentation at https://telepresence.io "
            "for more details.\n"
        )
        raise SystemExit(1)