Ask HN: Where do you go to request code reviews?

I'm not a professional developer but I'd like to:

1. Contribute to open source 2. Have someone tell me if and how my code sucks so I can improve. 3. Learn more Golang and move from basic/medium to advanced Python.

I'm having trouble with point 2. Yes, I can look at code from rockstar golang devs and read style guides but it's be so much more efficient if someone could review it and suggest improvements.

Is there a "as a service" for this? Some opensource organisation that does this for free in exchange to gathering metrics about people's code?

PS: I have a particular Go toy app I built, it's around 500 lines of code and on github.