In the constants.py file there is a variable called ETH_ADDRESS which has the value 0x0000000000000000000000000000000000000000.

This works fine for Uniswap and even Pancakeswap but doesn't work for polygon network because the ETH_ADDRESS for Polygon Network is 0x0000000000000000000000000000000000001010.

This affects make_trade methods if you want to buy/sell with MATIC as one of the token. Otherwise it works well.