code: def ancestors(self, node):
      self._check_node_in_graph(node)
  
      ancestors = set()
      for predecessor in self._predecessors[node]:
          ancestors.add(predecessor)
          ancestors |= self.ancestors(predecessor)
      return ancestors
  
file_path: baikal/baikal/_core/digraph.py
imports: from collections import deque, defaultdict, OrderedDict
label_desc: Use image node_id 11 for calling the DiGraph obj's underlying member method code with example usage: obj.ancestors(node) and returns: ancestors