def on_cleanup_error(function, path, excinfo):
                click.secho("warning: failed to remove file or directory: {}\n"
                            "please delete it manually.".format(path),
                            fg="red")
def getT(self):
        x = self.p2.x - self.p1.x
        y = self.p2.y - self.p1.y
        if (math.fabs(x) < math.pow(10,-100)):
            if(y < 0.0):
                return (-math.pi/2)
            else:
                return (math.pi/2)
        else:
            return math.atan2(y, x)