code: def _plt_pydot(self, fout_img):
          
          dag = self._get_pydot_graph()
          img_fmt = os.path.splitext(fout_img)[1][1:]
          dag.write(fout_img, format=img_fmt)
          self.log.write("  {GO_USR:>3} usr {GO_ALL:>3} GOs  WROTE: {F}\n".format(
              F=fout_img,
              GO_USR=len(self.godag.go_sources),
              GO_ALL=len(self.godag.go2obj)))
docs: Plot using the pydot graphics engine.