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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 constrained_by(self):
 """ returns a list of parameters that constrain this parameter """

        if self._is_constraint is None:
            return []
        params = []
        for var in self.is_constraint._vars:
            param = var.get_parameter()
            if param.uniqueid != self.uniqueid:
                params.append(param)
        return params