code: def GET_AUTH(self, courseid):  # pylint: disable=arguments-differ
          
          course, __ = self.get_course_and_check_rights(courseid, allow_all_staff=False)
  
          data = web.input()
  
          if "download" in data:
              filepath = os.path.join(self.backup_dir, courseid, data["download"] + '.zip')
  
              if not os.path.exists(os.path.dirname(filepath)):
                  raise web.notfound()
  
              web.header('Content-Type', 'application/zip', unique=True)
              web.header('Content-Disposition', 'attachment; filename="' + data["download"] + '.zip' + '"', unique=True)
  
              return open(filepath, 'rb')
  
          else:
              return self.page(course)
docs: GET request