Generate python code to create a system that tests trading strategies on financial market data, specifically for two$-$year Treasury futures $($ZT$).$ You'll need to design a framework that:

$1.$ Stores market data.

$2.$ Stores trading orders

$3.$ Tracks financial positions.

$4.$ Create a trading strategy $($abstract class$)$

$5.$ Create a mean$-$reverting strategy

$6.$ Build a backtesting engine

You will then use this system to test whether the trading strategy you choose can make a profit using historical data for a specific date.