'Set arbitrary query flags using a bitmask.
To set the tailable flag:
cursor.add_option(2)'

def add_option(self, mask):

    if (not isinstance(mask, int)):
        raise TypeError('mask    must    be    an    int')
    self.__check_okay_to_chain()
    if (mask & _QUERY_OPTIONS['exhaust']):
        if self.__limit:
            raise InvalidOperation("Can't    use    limit    and    exhaust    together.")
        if self.__collection.database.client.is_mongos:
            raise InvalidOperation('Exhaust    cursors    are    not    supported    by    mongos')
        self.__exhaust = True
    self.__query_flags |= mask
    return self
