code: def cropped(self, t0, t1):
          
          if abs(self.delta*(t1 - t0)) <= 180:
              new_large_arc = 0
          else:
              new_large_arc = 1
          return Arc(self.point(t0), radius=self.radius, rotation=self.rotation,
                     large_arc=new_large_arc, sweep=self.sweep,
                     end=self.point(t1), autoscale_radius=self.autoscale_radius)
docs: returns a cropped copy of this segment which starts at
          self.point(t0) and ends at self.point(t1).