code: def _fromMathInfo(self, mathInfo, guidelines=True):
          
          self.guidelines = []
          mathInfo.extractInfo(self)
          font = self.font
          if guidelines:
              for guideline in self.guidelines:
                  font.appendGuideline(
                      position=(guideline["x"], guideline["y"]),
                      angle=guideline["angle"],
                      name=guideline["name"],
                      color=guideline["color"]
                      # XXX identifier is lost
                  )
          del self.guidelines
docs: Subclasses may override this method.