title: Get github username by id
body: <p>Using this link I can see that my (tonylampada) id on github is 218821
  <a href="https://api.github.com/users/tonylampada">https://api.github.com/users/tonylampada</a></p>
  
  <p>How could I do the opposite? Given the user id = 218821, what's the username?</p>
  
  <hr>
  
  <p>Update</p>
  
  <p>Answering nulltoken here because it's a long story and it won't fit in a comment.</p>
  
  <p><a href="http://www.freedomsponsors.org/">FreedomSponsors</a> is a django application that uses django-social-auth to enable login with Github (and others).
  (You should check it out, btw, please see the <a href="http://blog.freedomsponsors.org/about">about page</a> in the blog :-)
  Django-social-auth has a configuration flag that allows the application to store the github username on the database.
  A few days ago I deployed a new version of FS with github login enabled, but with "storeGithubUsername" set to false.</p>
  
  <p>A few users registered their github accounts, and now the database has their github ids, but not their usernames.</p>
  
  <p>You can se in <a href="http://www.freedomsponsors.org/core/user/2/tonylampada">my profile</a> that I have github as a "connected account" but there's no link to my github page.</p>
  
  <p>I need it to make the link point to <a href="https://github.com/tonylampada">https://github.com/tonylampada</a></p>
  
  <p>I'm ready to deploy a new version that fixes this, by setting the "storeGithubUsername" (that's not what it is called, I'm just simplifying here) to true.
  But I'd like to patch the database with the already github-registered users. I have their github ids, but not their github usernames.</p>