How to Mock a Redis Transaction with MULTI/EXEC in Python

class RedisTransactionMock:
    def __init__(self):
        self.data = {}
        self.queue = []
        self.in_transaction = False

    def multi(self):
        self.in_transaction = True
        self.queue = []
        return "OK"

    def set(self, key, value):
        if self.in_transaction:
            self.queue.append(("set", key, value))
            return "QUEUED"
        self.data[key] = value
        return "OK"

    def get(self, key):
        if self.in_transaction:
            self.queue.append(("get", key))
            return "QUEUED"
        return self.data.get(key)

    def delete(self, key):
        if self.in_transaction:
            self.queue.append(("delete", key))
            return "QUEUED"
        self.data.pop(key, None)
        return "OK"

    def exec(self):
        if not self.in_transaction:
            return None
        results = []
        for command in self.queue:
            if command[0] == "set":
                self.data[command[1]] = command[2]
                results.append("OK")
            elif command[0] == "get":
                results.append(self.data.get(command[1]))
            elif command[0] == "delete":
                self.data.pop(command[1], None)
                results.append("OK")
        self.in_transaction = False
        self.queue = []
        return results

if __name__ == "__main__":
    r = RedisTransactionMock()
    r.multi()
    print(r.set("name", "Alice"))
    print(r.get("name"))
    print(r.set("age", 30))
    result = r.exec()
    print(result)
    print(r.get("name"))