Most efficient way to find ancestors of a node

What is the most efficient way to find the ancestors (parents) of a particular node?

You can find the “in” and “out” components of a node using the subcomponent function, e.g. G.subcomponent(v, mode=ig.IN). This functions returns all nodes that can reach the node v (when using ig.IN) or all nodes that can be reached by node v (when using ig.OUT).