def cropped(self, t0, t1):
        """returns a cropped copy of this segment which starts at
        self.point(t0) and ends at self.point(t1)."""
        return Line(self.point(t0), self.point(t1))
def cropped ( self , t0 , t1 ) : return Line ( self . point ( t0 ) , self . point ( t1 ) )
returns a cropped copy of this segment which starts at
        self.point(t0) and ends at self.point(t1).