def get(self, id, pk='id', deleted=False):
        try:
            if pk == 'id':
                id = int(id)
            if deleted:
                spec = {pk: id}
            else:
                spec = {pk: id, 'data': {'$exists': 1}}
            fields = {'_id': 0}
            row = self.db.docs.find_one(spec, fields)
        except Exception as e:
            raise DatabaseException(e)
        if row:
            return Document(**row)
        raise NotFoundError('%s %s not found' % (pk, id))
def _genSeq(self):
        self.raw_sequence = random.getrandbits(64)
        parts = []
        while self.raw_sequence:
            parts.append(self.raw_sequence & limit)
            self.raw_sequence >>= 32

        self.sequence = struct.pack('<' + 'L'*len(parts), *parts)
        # struct.unpack('<LL', '\xb1l\x1c\xb1\x11"\x10\xf4')
        return 0