quantra - A public API for quantitative finance made with Quantlib
QuantConnect - QuantConnect provides a free algorithm backtesting tool and financial data so engineers can design algorithmic trading strategies. We are democratizing algorithm trading technology to empower investors.
Pandas - Pandas is an open source library providing high-performance, easy-to-use data structures and data analysis tools for the Python.
Backtrader - Backtrader is a complete and advanced python framework that is used for backtesting and trading.
PyCharm - Python & Django IDE with intelligent code completion, on-the-fly error checking, quick-fixes, and much more...
Intrinio - Intrinio is a trading platform, providing professionals with the best in class financial market data API and other tools.