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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 apex2qd(self, alat, alon, height):
 """Converts modified apex to quasi-dipole coordinates. Parameters ========== alat : array_like Modified apex latitude alon : array_like Modified apex longitude height : array_like Altitude in km Returns ======= qlat : ndarray or float Quasi-dipole latitude qlon : ndarray or float Quasi-dipole longitude Raises ====== ApexHeightError if `height` > apex height """


        qlat, qlon = self._apex2qd(alat, alon, height)

        # if array is returned, the dtype is object, so convert to float
        return np.float64(qlat), np.float64(qlon)