def METHOD_NAME(self):
    PDBENSEMBLEB = PDBENSEMBLEA[:]
    PDBENSEMBLEB.iterpose()
    ensemble = PDBENSEMBLEB[:]
    ensemble.delCoordset(1)
    assert_equal(ensemble._trans,
                 PDBENSEMBLEB._trans[[0,2]],
                 'failed to delete middle transformation')