code: public function randMember($count = null)
      {
          $return = $this->redis->srandmember($this->key, $count);
  
          return \is_array($return) ? $this->unSerializeArray($return) : $this->unSerialize($return);
      }
docs: @param null $count Amount of members to randomly take from set.
  Positive: return $count distinct members.
  Negative: return -$count members. Can return elements multiple times. Fills until length of
  -$count.
  Zero: empty set.
  Null (default): return one element (not as set).
  
  @return mixed|mixed[] Array of or a single member of set.