Replace list on MLData

exa/exa/helpers/utilits.py

@@ -34,5 +34,8 @@ class MLDataMaker:
         for news_tag in news.tags.split(','):
             for i in self.tags:
                 if self.is_tag_similar(i.tags, news_tag):
-                    ml_data.append([news.id, i.id])
+                    ml_data.append(MLData(news.id, i.id))
+        if len(ml_data) > 0:
             return ml_data
+        else:
+            return None