@staticmethod
def setup_subparser(parser, cmd=None):
    """
        Set up a subparser for 'config'
        """
    parser.add_argument('key', nargs='?', help=
        'Configuration key to query or set')
    parser.add_argument('value', nargs='?', help='New value')
    parser.add_argument('-c', '--config-file', help=
        'Specify the config file to update')
    parser.add_argument('-o', '--config-only', action='store_true', help=
        'If specified, only consider options from this one file. Default: Consider all config options'
        )
    parser.add_argument('-P', '--package', help=
        'If specified, set options for this package instead of the global configs'
        )
    parser.add_argument('-C', '--category', help=
        'If specified, set options for this category instead of the global configs'
        )
    parser.add_argument('-E', '--env', action='store_true', default=None,
        help=
        'If specified, set an environment variable instead of the global configs'
        )
