code: function(request, modules_root, options){
          var [path, analysis] = normalize_path(request, modules_root, options.relative_path_root);
          var cache_path = path; // define cachepath as path to file with content. For modules, defines path to package.json
          if(analysis.is_a_module) cache_path = "module:" + cache_path; // since modules return package.json request, distinguish between module requests and actual requests to package.json
          return cache_path;
      }
docs: list of unique cache_paths for self analysis /*
  methods