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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 from_(cls, dic):
 """ Build a new ParamSet from a dictionary of string-valued parameters which are assumed to be already valid. """

        self = cls.__new__(cls)
        for k, v in dic.items():
            setattr(self, k, ast.literal_eval(v))
        return self