def r_collections(self, lang=None):
collection = self.resolver.getMetadata()<EOL>return {<EOL>"<STR_LIT>": "<STR_LIT>",<EOL>"<STR_LIT>": collection.get_label(lang),<EOL>"<STR_LIT>": {<EOL>"<STR_LIT>": self.make_members(collection, lang=lang)<EOL>}<EOL>}<EOL>
Retrieve the top collections of the inventory

        :param lang: Lang in which to express main data
        :type lang: str
        :return: Collections information and template
        :rtype: {str: Any}