def __init__(self, storage, schema = None, indexname = _DEF_INDEX_NAME):
        """
        :param storage: The :class:`whoosh.store.Storage` object in which this index resides.
            See the store module for more details.
        :param schema: A :class:`whoosh.fields.Schema` object defining the fields of this index.
        :param indexname: An optional name to use for the index. Use this if you need
            to keep multiple indexes in the same storage object.
        """
        
        self.storage = storage
        self.indexname = indexname
        
        if schema is not None and not isinstance(schema, fields.Schema):
            raise ValueError(schema % "%r is not a Schema object")
        
        self.schema = schema
dataset/ETHPy150Open dokipen/whoosh/src/whoosh/index.py/Index.__init__/swapped operands of `%`