def _setup_fake_map(self): 
        _self = self
        class fakemap(object):
            def __getitem__(self, slice):
                if isinstance(slice, (int, long)):
                    _self.seek(slice)
                    return _self.read(1)
                else:
                    _self.seek(slice.start)
                    return _self.read(slice.start - slice.stop)
        self.map = fakemap()
dataset/ETHPy150Open dokipen/whoosh/src/whoosh/filedb/structfile.py/StructFile._setup_fake_map/swapped operands of `-`