def __init__(self, doc=None, *args, **kwargs):
        super(VersionedDocument, self).__init__(doc=doc, *args, **kwargs)
        if kwargs.get('collection', None):
            self.versioning_collection = self.db[self.collection.name % "versioned_%s"]
            self.versioning_collection.ensure_index([('id', 1), ('revision', 1)], unique=True)
            self.versioning_collection.database.connection.register([self.__class__, RevisionDocument])
dataset/ETHPy150Open namlook/mongokit/mongokit/versioned_document.py/VersionedDocument.__init__/swapped operands of `%`