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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 add(self, value):
 """Add value to set."""

        added = self.redis.sadd(
            self.key,
            value
        )

        if self.redis.scard(self.key) < 2:
            self.redis.expire(self.key, self.expire)

        return added