docs: def get_recipe_instances_for_badges(self, badges):
          """
          Takes a list of badge slugs and returns a tuple: ``(valid, invalid)``.
          """
          from .exceptions import BadgeNotFound
  
          valid, invalid = [], []
  
          if not isinstance(badges, (list, tuple)):
              badges = [badges]
  
          for badge in badges:
              try:
                  recipe = self.get_recipe_instance(badge)
                  valid.append(recipe)
              except BadgeNotFound:
                  logger.debug('✘ Badge "%s" has not been registered', badge)
                  invalid.append(badge)
  
          return (valid, invalid)