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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 nan_pixels(self):
 """ Return an array of the NaN pixels. Returns ------- :obj:`numpy.ndarray` Nx2 array of the NaN pixels """

        nan_px = np.where(np.isnan(np.sum(self.raw_data, axis=2)))
        nan_px = np.c_[nan_px[0], nan_px[1]]
        return nan_px