key <AC06> { [ h, H, parenleft, parenleft ] };

key <AC06> { [ h, H, parenleft, bracketleft ] };

partial default xkb_types "default" {

    // Definition for a key type which
    // can be used to implement ISO9995
    // style level three shift
    virtual_modifiers LevelThree;

    type "THREE_LEVEL" {
        modifiers = Shift+LevelThree;
        map[None] = Level1;
        map[Shift] = Level2;
        map[LevelThree] = Level3;
        map[Shift+LevelThree] = Level3;
        level_name[Level1] = "Base";
        level_name[Level2] = "Shift";
        level_name[Level3] = "Level3";
    };
};

partial default xkb_types "default" {
    // Definition for a key type used for the czech keymap, for instance.
    // Defines style a with four level shift. It is similar to three_level
    // type used for iso9995 but it lets the shift key behave "normally".

    virtual_modifiers LevelThree;

    type "FOUR_LEVEL" {
        modifiers = Shift+LevelThree;
        map[None] = Level1;
        map[Shift] = Level2;
        map[LevelThree] = Level3;
        map[Shift+LevelThree] = Level4;
        level_name[Level1] = "Base";
        level_name[Level2] = "Shift";
        level_name[Level3] = "Alt Base";
        level_name[Level4] = "Shift Alt";
    };
[...]

partial alphanumeric_keys
xkb_symbols "us" {
    include "nokia_vndr/rx-51(english_base)"
    include "nokia_vndr/rx-51(arrows_4btns)"

    name[Group1] = "U.S. English";
    key.type[Group1] = "FOUR_LEVEL";
   
    // 1. row

    // 2. row
    key <AC06>	{ [h,	H, parenleft, bracketleft ] };
    key <AC07>	{ [j,	J, parenright, bracketright ] };

    // 3. row
};