public ActionResult <bool> CheckLabelExists(string label)
 {
     try
     {
         var hashtag = _hashtagService.GetByLabel(label);
         return(true);
     }
     catch (HashtagNotFoundException)
     {
         return(false);
     }
 }
        public ActionResult <IEnumerable <TweetDto> > GetTaggedTweets(string label)
        {
            var hashtag = _hashtagService.GetByLabel(label);

            return(_mapper.Map <IEnumerable <TweetDto> >(_hashtagService.GetTaggedTweets(hashtag)).ToList());
        }