def provider_parser(subparser):
    """Configure provider parser for Rackspace"""
    subparser.add_argument('--auth-account', help=
        'specify account number for authentication')
    subparser.add_argument('--auth-username', help=
        'specify username for authentication. Only used if --auth-token is empty.'
        )
    subparser.add_argument('--auth-api-key', help=
        'specify api key for authentication. Only used if --auth-token is empty.'
        )
    subparser.add_argument('--auth-token', help=
        'specify token for authentication. If empty, the username and api key will be used to create a token.'
        )
    subparser.add_argument('--sleep-time', type=float, default=1, help=
        'number of seconds to wait between update requests.')
