def __mul__(self, point):
        """
        Cross product
        """

        p = Point()

        p.x = self.y * point.z - self.z * point.y
        p.y = self.z * point.x - self.x * point.z
        p.z = self.x * point.y - self.y * point.x

        return p
def __mul__ ( self , point ) : p = Point ( ) p . x = self . y * point . z - self . z * point . y p . y = self . z * point . x - self . x * point . z p . z = self . x * point . y - self . y * point . x return p
Cross product