[bugfix] Fix srandmember(key, 0) returns 1 element bug
[bugfix] Fix srandmember(key, 0) returns 1 element bug

redis/redis-py,andymccurdy/redis-py,mozillazg/redis-py-doc,5977862/redis-py,alisaifee/redis-py,andymccurdy/redis-py,5977862/redis-py,5977862/redis-py,mozillazg/redis-py-doc,andymccurdy/redis-py,alisaifee/redis-py,redis/redis-py