def test_MODS(sentence: nnf.Or):
assert sentence.smooth()
assert sentence.flat()
assert sentence.decomposable()
assert sentence.simply_conjunct()
def test_hyp(sentence: nnf.Or):
assume(len(sentence.children) != 0)
assume(sentence.decomposable())
assert sentence.satisfiable()
assert sentence.vars() <= set(range(1, 9))