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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 serve_forever(self):
 """Call the main loop."""

        # Set the server login/password (if -P/--password tag)
        if self.args.password != "":
            self.add_user(self.args.username, self.args.password)
        # Serve forever
        self.server.serve_forever()