qmk_firmware/keyboards/christmas_tree/christmas_tree.h

#pragma once

#include "quantum.h"

#define LAYOUT( \
    k00, k10, k20, k30, k40, k50 \
) { \
    { k00 }, \
    { k10 }, \
    { k20 }, \
    { k30 }, \
    { k40 }, \
    { k50 } \
}