Hi, may I know whats the proper way to construct TradeBuilder to use FlatToFlat? 

The default uses FillToFill. I can't overwrite TradeBuilder property in QCAlgorithm because its a 'private set'.

I tried to override TradeBuilder using a subclass but the algo instance retrieve from the assembly still uses the QCAlgo's TradeBuilder instead of the subclass TradeBuilder. Consequently, trades are not captured in my strategy. Am I missing something? Is there an easier way to change fill method?

Thank you.

Novice programmer

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