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

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