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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 update(self, display_name=None, display_description=None):
 """ Update the specified values on this snapshot. You may specify one or more values to update. If no values are specified as non-None, the call is a no-op; no exception will be raised. """

        return self.manager.update(self, display_name=display_name,
                display_description=display_description)