a = [{'a':1,'time':'2021-03-01'},{'a':3,'time':'2021-03-11'}]
for item in a:
        try:created_at = time.strftime('%Y-%m-%d %H:%M:%S',time.strptime(item.time,"%Y-%m-%d %H:%M:%S"))
        except:
            try:created_at = time.strftime('%Y-%m-%d %H:%M:%S',time.strptime(item.time,"%Y-%m-%d %H:%M"))
            except:created_at = time.strftime('%Y-%m-%d %H:%M:%S',time.strptime(item.time,"%Y-%m-%d"))
        data.append({"keyword":item.keyword,"task_id":item.task_id,"title":item.text,"author":item.author,"username":item.author_href,
                    "created_at":created_at,"index_href":item.article_href,"source":"Facebook"})
    data.sort(key=lambda x:(x['created_at']))
    data.reverse()