code: def get_topological_order(self, cfg_node):
          
  
          if not self._quasi_topological_order:
              self._quasi_topological_sort()
  
          return self._quasi_topological_order.get(cfg_node, None)
docs: Get the topological order of a CFG Node.
  
          :param cfg_node: A CFGNode instance.
          :return: An integer representing its order, or None if the CFGNode does not exist in the graph.