def addUser(self, user):
        if user.name in self.users:
            return defer.fail(failure.Failure(ewords.DuplicateUser()))
        self.users[user.name] = user
        return defer.succeed(user)
dataset/ETHPy150Open kuri65536/python-for-android/python-modules/twisted/twisted/words/service.py/InMemoryWordsRealm.addUser/original