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

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