def retract(self, sentence):
        "Remove the sentence's clauses from the KB."
        for c in conjuncts(to_cnf(sentence)):
            if c in self.clauses:
                self.clauses.remove(c)
def retract(self, sentence):
        "Remove the sentence's clauses from the KB."
        for c in conjuncts(to_cnf(sentence)):
            if c in self.clauses:
                self.clauses.remove(c)
def retract ( self , sentence ) : for c in conjuncts ( to_cnf ( sentence ) ) : if c in self . clauses : self . clauses . remove ( c )
Remove the sentence's clauses from the KB.
Remove the sentence s clauses from the KB .