code: def findNode(class_, hot_map, targetNode, parentNode=None):
          ''' Find the target node in the hot_map. '''
          for index, (rect, node, children) in enumerate(hot_map):
              if node == targetNode:
                  return parentNode, hot_map, index
              result = class_.findNode(children, targetNode, node)
              if result:
                  return result
          return Nonf findNode(class_, hot_map, targetNode, parentNode=None):
          ''' Find the target node in the hot_map. '''
          for index, (rect, node, children) in enumerate(hot_map):
              if node == targetNode:
                  return parentNode, hot_map, index
              result = class_.findNode(children, targetNode, node)
              if result:
                  return result
          return None
docs: Find the target node in the hot_map.