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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 satisfy_one(self, assumptions=None, **params):
 """ If the input CNF is satisfiable, return a satisfying input point. A contradiction will return None. """

        verbosity = params.get('verbosity', 0)
        default_phase = params.get('default_phase', 2)
        propagation_limit = params.get('propagation_limit', -1)
        decision_limit = params.get('decision_limit', -1)
        seed = params.get('seed', 1)
        return picosat.satisfy_one(self.nvars, self.clauses, assumptions,
                                   verbosity, default_phase, propagation_limit,
                                   decision_limit, seed)