code: def run_node(self, node, stim):
          ''' Executes the Transformer at a specific node.
  
          Args:
              node (str, Node): If a string, the name of the Node in the current
                  Graph. Otherwise the Node instance to execute.
              stim (str, stim, list): Any valid input to the Transformer stored
                  at the target node.
          '''
          if isinstance(node, string_types):
              node = self.nodes[node]
  
          result = node.transformer.transform(stim)
          if node.is_leaf():
              return listify(result)
  
          stim = result
          # If result is a generator, the first child will destroy the
          # iterable, so cache via list conversion
          if len(node.children) > 1 and isgenerator(stim):
              stim = list(stim)
          return list(chain(*[self.run_node(c, stim) for c in node.children])f run_node(self, node, stim):
          ''' Executes the Transformer at a specific node.
  
          Args:
              node (str, Node): If a string, the name of the Node in the current
                  Graph. Otherwise the Node instance to execute.
              stim (str, stim, list): Any valid input to the Transformer stored
                  at the target node.
          '''
          if isinstance(node, string_types):
              node = self.nodes[node]
  
          result = node.transformer.transform(stim)
          if node.is_leaf():
              return listify(result)
  
          stim = result
          # If result is a generator, the first child will destroy the
          # iterable, so cache via list conversion
          if len(node.children) > 1 and isgenerator(stim):
              stim = list(stim)
          return list(chain(*[self.run_node(c, stim) for c in node.children]))
docs: Executes the Transformer at a specific node.
  
          Args:
              node (str, Node): If a string, the name of the Node in the current
                  Graph. Otherwise the Node instance to execute.
              stim (str, stim, list): Any valid input to the Transformer stored
                  at the target node.