def insert(self, doc, synced=False):
        doc.id = self.get_next_id()
        doc.synced = synced
        try:
            self.db.docs.insert(doc)
        except Exception as e:
            raise DatabaseException(e)
        return doc
def get_probabilities(self):
        """!
        @brief Returns 2-dimensional list with belong probability of each object from data to cluster correspondingly,
                where that first index is for cluster and the second is for point.