def equiv(self, other, prover=None):
        assert isinstance(other, Expression), "%s is not an Expression" % other

        if prover is None:
            from nltk.inference import Prover9
            prover = Prover9()
        bicond = IffExpression(self.simplify(), other.simplify())
        return prover.prove(bicond)
Check for logical equivalence.
dataset/ETHPy150Open nltk/nltk/nltk/sem/logic.py/Expression.equiv