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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 _version_view(self):
 """ View that returns the contents of version.json or a 404. """

        version_json = self._version_callback(self.version_path)
        if version_json is None:
            return 'version.json not found', 404
        else:
            return jsonify(version_json)