code: def inverse(self):
          
          new = self.conjugate()
          tmp = self.norm()**2
          new.w /= tmp
          new.x /= tmp
          new.y /= tmp
          new.z /= tmp
          return new
docs: returns q.conjugate()/q.norm()**2
          
          So if the quaternion is unit length, it is the same
          as the conjugate.