public void AddOrUpdate(string key, RequestFree requestFree)
 {
     if (!Requests.TryAdd(key, requestFree))
     {
         Requests[key] = requestFree;
     }
 }
 public bool Add(string key, RequestFree requestFree)
 {
     return(Requests.TryAdd(key, requestFree));
 }
 public void AddOrUpdate(string key, RequestFree requestFree)
 {
     Requests[key] = requestFree;
 }