docs: function(key) {
  
            // First check to see if it's the object cache
            var cached = objectCache[key];
            if (cached) {
              return cached;
            }
  
            // Deserialize the object from JSON
            var json = persistenceStrategy.get(key);
  
            // null or undefined --> return null.
            if (json == null) {
              return null;
            }
  
            try {
              return JSON.parse(json);
            } catch (err) {
              return null;
            }
          }