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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 getSchema(cls):
 """ return all persistent class attributes """

        schema = []
        for name, atr in cls.__attributes__:
            atr = atr.__get__(None, cls)
            if isinstance(atr, SQLAttribute):
                schema.append((name, atr))
        cls.getSchema = staticmethod(lambda schema=schema: schema)
        return schema