A sibling comment already pointed this out, but the existence of https://code.go...

scott_s on March 12, 2015 | parent | context | favorite | on: Bidding farewell to Google Code

A sibling comment already pointed this out, but the existence of https://code.google.com/export-to-github/ and its explicit mention in the post along with the clear language that they did work with GitHub and Bitbucket, leads me to believe that you did not read the post.