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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 enable(self):
 """ Enable antivirus on the engine """

        self.update(antivirus_enabled=True,
                    virus_mirror='update.nai.com/Products/CommonUpdater' if \
                        not self.get('virus_mirror') else self.virus_mirror,
                    antivirus_update_time=self.antivirus_update_time if \
                        self.get('antivirus_update_time') else 21600000)