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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 invert(self):
 """ Invert the keys and values of an object. The values must be serializable. """

        keys = self._clean.keys()
        inverted = {}
        for key in keys:
            inverted[self.obj[key]] = key

        return self._wrap(inverted)