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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 get_ticket(self, request):
 """Called to return the ticket for a request. Args: request: aiohttp Request object. Returns: A ticket (string like) object, or None if no ticket is available for the passed request. """

        session = await get_session(request)
        return session.get(self.cookie_name)