Earlier quoted context omitted.
I disagree. Python is great for scripting and for small projects, but I believe strong, static typing is an essential feature for large scale projects. I wouldn't want to use Python for anything that's predicted to end up with more than a couple thousand lines of code.
Instagram would disagree with you. Seriously, Python is an absolute pleasure for managing large web projects and the lack of static typing has never been an issue for my company (spend the time writing tests instead!)
That's what the vast majority of testing is when it isn't simply testing mock code implementations.