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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 constraint_df(self):
 """ A DataFrame representing all constraints, hidden or not """

        df = pd.DataFrame()
        for name,c in self.constraints.items():
            df[name] = c.ok
        for name,c in self.hidden_constraints.items():
            df[name] = c.ok
        return df