python FIFO stock portfolio calculations

I'm calculating returns for a stock portfolio with hundreds of symbols over a period of many years. I need to evaluate the tax efficiency of this portfolio, which means that I need to account for stock purchases and sales according to FIFO rules of accounting. If I buy a stock and sell it in less than a year, then I pay one tax rate, but if I hold it for over 1 year, I pay a different tax rate. So, for every date, I'd like to calculate the long-term and short-term capital gains for the portfolio from the trades that happen on that date. I'm trying to think of an efficient way to perform these calculations. Ideally, this would be something that would operate on a Pandas DataFrame that contains all of the trades. Perhaps someone knows of a open source portfolio app that already does this? Thanks.