Here’s a tool I stumbled upon -
Nullege is a search engine for Python source code.
Nullege apparently lists 65,000+ Python projects!
Edit: so http links work!?
http://nullege.com/pages/about
http://nullege.com/codes/search?cq=erpnext
http://nullege.com/codes/search?cq=frappe
Disclaimer: I have no affiliation with Nullege or it’s promoters