code: def qcurve(self, vertexes, attr=0, row=None):
          'quadratic curve from vertexes[0] to vertexes[2] with control point at vertexes[1]'
          assert len(vertexes) == 3, len(vertexes)
          x1, y1 = vertexes[0]
          x2, y2 = vertexes[1]
          x3, y3 = vertexes[2]
  
          self.point(x1, y1, attr, row)
          self._recursive_bezier(x1, y1, x2, y2, x3, y3, attr, row)
          self.point(x3, y3, attr, rowf qcurve(self, vertexes, attr=0, row=None):
          'quadratic curve from vertexes[0] to vertexes[2] with control point at vertexes[1]'
          assert len(vertexes) == 3, len(vertexes)
          x1, y1 = vertexes[0]
          x2, y2 = vertexes[1]
          x3, y3 = vertexes[2]
  
          self.point(x1, y1, attr, row)
          self._recursive_bezier(x1, y1, x2, y2, x3, y3, attr, row)
          self.point(x3, y3, attr, row)
docs: quadratic curve from vertexes[0] to vertexes[2] with control point at vertexes[1]