What is the best composition for 2 vs 2 ?

Hello everyone, I am doing a 2 vs 2 tournament tomorow and with my friend we were searching for a good composition.

We will have 5 ban for each team, the game ends when there are 2 kills or 1 turret down or 100 cs in a team. We will play on Howling abyss.

Thanks in advance !