code: def str_to_dot(string):
      """
      Converts input string from graphviz library to valid DOT graph format.
  
      :param string: Graph in DOT format.
      :returns: DOT string converted to a suitable format for the DoWhy library.
      """
      graph = string.strip().replace("\n", ";").replace("\t", "")
      graph = (
          graph[:9] + graph[10:-2] + graph[-1]
      )  # Removing unnecessary characters from string
      return graph
  
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 3 for calling a global function with example usage: str_to_dot(string) and returns: graph