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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 add_relation(self, local_relation, remote_relation):
 """Add a relation to another application. :param str local_relation: Name of relation on this application :param str remote_relation: Name of relation on the other application in the form '<application>[:<relation_name>]' """

        if ':' not in local_relation:
            local_relation = '{}:{}'.format(self.name, local_relation)

        return await self.model.add_relation(local_relation, remote_relation)