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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 append(self, name, value):
 """ Appends the string ``value`` to the value at ``key``. If ``key`` doesn't already exist, create it with a value of ``value``. Returns the new length of the value at ``key``. :param name: str the name of the redis key :param value: str :return: Future() """

        with self.pipe as pipe:
            return pipe.append(self.redis_key(name),
                               self.valueparse.encode(value))