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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 json_filter(self):
 """ filter out properties that have names starting with _ or properties that have a value of None """

        return lambda obj: dict((k, v) for k, v in obj.__dict__.items()
                                if not k.startswith('_') and getattr(obj, k) is not None)