@classmethod
def usage(cls):
    """Print usage of provider."""
    print(f'{cls.__doc__} Supported query types:')
    for ioc_key in sorted(cls._IOC_QUERIES):
        ioc_key_elems = ioc_key.split('-', maxsplit=1)
        if len(ioc_key_elems) == 1:
            print(f'\tioc_type={ioc_key_elems[0]}')
        if len(ioc_key_elems) == 2:
            print(
                f'\tioc_type={ioc_key_elems[0]}, ioc_query_type={ioc_key_elems[1]}'
                )
