code: def r_collection(self, objectId, lang=None):
          
          collection = self.resolver.getMetadata(objectId)
          return {
              "template": "main::collection.html",
              "collections": {
                  "current": {
                      "label": str(collection.get_label(lang)),
                      "id": collection.id,
                      "model": str(collection.model),
                      "type": str(collection.type),
                  },
                  "members": self.make_members(collection, lang=lang),
                  "parents": self.make_parents(collection, lang=lang)
              },
          }
docs: Collection content browsing route function
  
          :param objectId: Collection identifier
          :type objectId: str
          :param lang: Lang in which to express main data
          :type lang: str
          :return: Template and collections contained in given collection
          :rtype: {str: Any}