(self, referrer: '_CachedRelation')
Add a reference from referrer to self, indicating that if this node
        were drop...cascaded, the referrer would be dropped as well.

        :param _CachedRelation referrer: The node that refers to this node.
Add a reference from referrer to self, indicating that if this node
        were drop...cascaded, the referrer would be dropped as well.
Add a reference from referrer to self indicating that if this node were drop ... cascaded the referrer would be dropped as well .
def add_reference(self, referrer: '_CachedRelation'):
        """Add a reference from referrer to self, indicating that if this node
        were drop...cascaded, the referrer would be dropped as well.

        :param _CachedRelation referrer: The node that refers to this node.
        """
        self.referenced_by[referrer.key()] = referrer
def add_reference ( self , referrer : '_CachedRelation' ) : self . referenced_by [ referrer . key ( ) ] = referrer