def main(argv=None):
    """Run dvc CLI command.

    Args:
        argv: optional list of arguments to parse. sys.argv is used by default.

    Returns:
        int: command's return code.
    """
    args = None
    cmd = None

    try:
        args = parse_args(argv)

        if args.quiet:
            logger.setLevel(logging.CRITICAL)

        elif args.verbose:
            logger.setLevel(logging.DEBUG)

        cmd = args.func(args)
        ret = cmd.run_cmd()
    except KeyboardInterrupt:
        logger.exception("interrupted by the user")
        ret = 252
    except NotDvcRepoError:
        logger.exception("")
        ret = 253
    except DvcParserError:
        ret = 254
    except Exception:  # pylint: disable=broad-except
        logger.exception("unexpected error")
        ret = 255

    Analytics().send_cmd(cmd, args, ret)

    return ret
Run dvc CLI command.

    Args:
        argv: optional list of arguments to parse. sys.argv is used by default.

    Returns:
        int: command's return code.