code: function returnCache(cache) {
  	let text = '';
  
  	for (const key in cache) {
  		if (!cache.hasOwnProperty(key)) {
  			continue;
  		}
  
  		text += cache[key];
  	}
  
  	return text;
  }
docs: Returns a cache string by an object
  
  @param {?} cache - cache object
  @return {string}