It really depends on your domain. I haven't seen C# a lot, nor python, in some orgs.

For some (like me), it's more a superset of C, assembly, bash, maybe lisp, python and matlab.

For others, it's going to be JavaScript, PHP, CSS, HTML..

I agree though that a library is usually domain-specific, and that you can probably easily identify the subset of languages that you really need official bindings for (thereby making my comment a bit useless, sorry for the noise).