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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 reduce(self, op):
 """Reduce the raster to a score, using 'op' operation. nodata pixels are ignored. op is currently limited to numpy.ma, e.g. 'mean', 'std' etc :returns list of per-band values """

        per_band = [getattr(np.ma, op)(self.image.data[band, np.ma.getmaskarray(self.image)[band, :, :] == np.False_])
                    for band in range(self.num_bands)]
        return per_band