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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 _best_res_pixels(self):
 """ Returns a numpy array of all the HEALPix indexes contained in the MOC at its max order. Returns ------- result : `~numpy.ndarray` The array of HEALPix at ``max_order`` """

        factor = 2 * (AbstractMOC.HPY_MAX_NORDER - self.max_order)
        pix_l = []
        for iv in self._interval_set._intervals:
            for val in range(iv[0] >> factor, iv[1] >> factor):
                pix_l.append(val)

        return np.asarray(pix_l)