code: def find_predecessor(i, j, g):
      """
      Finds a predecessor, k, in the path between two nodes, i and j,
      in the graph, g.
      """
      parents = list(g.predecessors(j))
      u = convert_to_undirected_graph(g)
      for pa in parents:
          try:
              path = shortest_path(u, pa, i)
              return pa
          except:
              pass
      return None
  
imports: import re
  from queue import LifoQueue
  import networkx
  import numpy
  from networkx.algorithms.dag import is_directed_acyclic_graph
  from networkx.algorithms.shortest_paths.generic import shortest_path
  from dowhy.utils.ordered_set import OrderedSet
label_desc: Use image node_id 12 for calling a global function with example usage: find_predecessor(i, j, g) and returns: None, pa