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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(self):
 """ Return an object representing the return json for the request """

        try:
            return self._json
        except AttributeError:
            try:
                self._json = json.loads(self.text)
                return self._json
            except:  # noqa e722
                raise RequestInvalidJSON("Invalid JSON received")