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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def inv(self):
 """Invert the transform. After calling this method, calling the instance will do the inverse transform. Calling this twice return the instance to the original transform. """


        self.x, self.y = self.y, self.x
        self._x_, self._y_ = self._y_, self._x_
        self.xfac, self.yfac = 1 / self.yfac, 1 / self.xfac
        self._xfac_, self._yfac_ = 1 / self._yfac_, 1 / self._xfac_
        self._u = 1 / self._u.conj()