get_sortable_columns example

$column_headers[ $key ] = $value;
            }

            $this->_column_headers = $column_headers;

            return $this->_column_headers;
        }

        $columns = get_column_headers( $this->screen );
        $hidden  = get_hidden_columns( $this->screen );

        $sortable_columns = $this->get_sortable_columns();
        /** * Filters the list table sortable columns for a specific screen. * * The dynamic portion of the hook name, `$this->screen->id`, refers * to the ID of the current screen. * * @since 3.1.0 * * @param array $sortable_columns An array of sortable columns. */
        $_sortable = apply_filters( "manage_{$this->screen->id}_sortable_columns", $sortable_columns );