using MongoClient instead of the deprecated Mongo class
changed content in print statement
added a TODO
added comment for the class
removed the use of shard. Predicate was earlier in DB-1 of Redis. Now it
is no longer the case. It is in DB-0.
removed the use of getShard(). Predicate was earlier in DB-1 of Redis.
Now it is no longer the case. It is in DB-0.