code: def check_key(request):
      
      try:
          access_key = request.session.get('oauth_token', None)
          if not access_key:
              return False
      except KeyError:
          return False
      return True
docs: Check to see if we already have an access_key stored,
      if we do then we have already gone through
      OAuth. If not then we haven't and we probably need to.