code: def _register_renderers(self, attrs):
          
          for method in attrs:
              func = getattr(self, method)
              mimetypes = getattr(func, 'mimetypes', [])
              for mimetype in mimetypes:
                  if not '/' in mimetype:
                      self.reject_map[mimetype] = func
                  if mimetype not in self.render_map:
                      self.render_map[mimetype] = func
                  else:
                      # about to redefine an already defined renderer.
                      # make sure this new render method is not on a base class.
                      base_classes = self.__class__.mro()[1:]
                      from_baseclass = any([x for x in base_classes if func.__name__ in dir(x)])
                      if not from_baseclass:
                          self.render_map[mimetype] = func
docs: Go through the passed in list of attributes and register those renderers
          in the render map.