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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:
 async def controller(self):
 """Return a Connection to the controller at self.endpoint """

        return await Connection.connect(
            self.endpoint,
            username=self.username,
            password=self.password,
            cacert=self.cacert,
            bakery_client=self.bakery_client,
            loop=self.loop,
            max_frame_size=self.max_frame_size,
        )