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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 qd2apex(self, qlat, qlon, height):
 """Converts quasi-dipole to modified apex coordinates. Parameters ========== qlat : array_like Quasi-dipole latitude qlon : array_like Quasi-dipole longitude height : array_like Altitude in km Returns ======= alat : ndarray or float Modified apex latitude alon : ndarray or float Modified apex longitude Raises ====== ApexHeightError if apex height < reference height """


        alat, alon = self._qd2apex(qlat, qlon, height)

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