code: def highlightVertex(self, i, action):
      self._highlightIndex = i
      self._highlightMode = action
  
imports: import math
  import sys
  from PyQt5.QtCore import QPointF
  from PyQt5.QtGui import QColor, QPen, QPainterPath, QFont
  from libs.utils import distance
label_desc: Use image node_id 19 for calling the Shape obj's underlying member method code with example usage: obj.highlightVertex(i, action) without return types