Returns the scores associated with the specified members in the sorted set stored at key.
For every member that does not exist in the sorted set, a nil value is returned.
Examples
127.0.0.1:6379> ZADD myzset 1 "one"
(integer) 1
127.0.0.1:6379> ZADD myzset 2 "two"
(integer) 1
127.0.0.1:6379> ZMSCORE myzset "one" "two" "nofield"
1) "1"
2) "2"
3) (nil)