Custom rule for Karabiner(KeyRemap4MacBook) to select the second/third candidate using left/right shift key only in Chinese Simplified input source

private.xml

<?xml version="1.0"?>
<root>
    <item>
        <name>Select the second/third candidate using left/right shift key.(only in Chinese-Simplified-*)</name>
        <identifier>private.select_candidate_using_shift_key</identifier>
        <inputsource_only>CHINESE_SIMPLIFIED</inputsource_only>
        <autogen>__KeyOverlaidModifier__ KeyCode::SHIFT_L, KeyCode::SHIFT_L, KeyCode::KEY_2</autogen>
        <autogen>__KeyOverlaidModifier__ KeyCode::SHIFT_R, KeyCode::SHIFT_R, KeyCode::KEY_3</autogen>
    </item>
</root>