code: protected function pluckMeta(Builder $query, ArgumentBag $args, $alias)
      {
          list($column, $key) = [$args->get('column'), $args->get('key')];
  
          $query->select("{$alias}.meta_value as {$column}");
  
          if (!is_null($key)) {
              $this->metaSelectListsKey($query, $key);
          }
  
          return $query->callParent('pluck', $args->all());
      }
docs: Get an array with the values of given meta attribute.
  
  @param  \Sofa\Eloquence\Builder $query
  @param  \Sofa\Hookable\Contracts\ArgumentBag $args
  @param  string $alias
  @return array