code: public long countByLex(final LexRange lexRange) {
          return doWithJedis(new JedisCallable<Long>() {
              @Override
              public Long call(Jedis jedis) {
                  return jedis.zlexcount(getKey(), lexRange.from(), lexRange.to());
              }
          });
      }
docs: When all the elements in a sorted set are inserted with the same score, in order to force lexicographical
  ordering, this command returns the number of elements in the sorted set with a value in the given range.
  @param lexRange
  @return the number of elements in the specified range.