code: def __str__(self):
      s = "(%3d,%3d) x=%s" % (self.layer, self.pos, str(self.x))
      if self.dummy:
          s = "[d] %s" % s
      return s
  
imports: from typing import Optional
label_desc: Use image node_id 2 for calling the LayoutVertex obj's underlying member method code with example usage: obj.__str__() and returns: s