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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 _unpack_v2(h5file, stage):
    '''Unpack groups from HDF5 v2 file'''
    points = np.array(h5file['neuron1/%s/points' % stage])
    # from documentation: The /neuron1/structure/unraveled reuses /neuron1/structure/raw
    groups_stage = stage if stage != 'unraveled' else 'raw'
    groups = np.array(h5file['neuron1/structure/%s' % groups_stage])
    stypes = np.array(h5file['neuron1/structure/sectiontype'])
    groups = np.hstack([groups, stypes])
    groups[:, [1, 2]] = groups[:, [2, 1]]
    return points, groups