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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 reduce(self):
 """Reduce to a canonical form."""

        support = frozenset(range(1, self.nvars+1))
        new_clauses = set()
        for clause in self.clauses:
            vs = list(support - {abs(uniqid) for uniqid in clause})
            if vs:
                for num in range(1 << len(vs)):
                    new_part = {v if bit_on(num, i) else ~v
                                for i, v in enumerate(vs)}
                    new_clauses.add(clause | new_part)
            else:
                new_clauses.add(clause)
        return self.__class__(self.nvars, new_clauses)