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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 read_seg(self, parc_type='aparc'):
 """Read the MRI segmentation. Parameters parc_type : str 'aparc' or 'aparc.a2009s' Returns ------- numpy.ndarray 3d matrix with values numpy.ndarray 4x4 affine matrix """

        seg_file = self.dir / 'mri' / (parc_type + '+aseg.mgz')
        seg_mri = load(seg_file)
        seg_aff = seg_mri.affine
        seg_dat = seg_mri.get_data()
        return seg_dat, seg_aff