<?py for board in set().union(global_boards, board_bans.keys()): ?>
location /#{board}/ {
    <?py if board in global_boards: ?>
    if ($bans_global) { rewrite ^ /cgi/banned; }
    <?py #endif ?>
    <?py if board in board_bans: ?>
    if ($bans_#{board}) { rewrite ^ /cgi/banned; }
    <?py #endif ?>
}
<?py #endfor ?>