如何从嵌套字典中通过值获取字典键？

def get_keys_from_value(dictionary, value):
    keys = []
    for k, v in dictionary.items():
        if v == value:
            keys.append(k)
        elif isinstance(v, dict):
            nested_keys = get_keys_from_value(v, value)
            if nested_keys:
                keys.extend([f"{k}.{nested_key}" for nested_key in nested_keys])
    return keys

nested_dict = {
    'a': {
        'b': {
            'c': 1,
            'd': 2
        },
        'e': {
            'f': 2,
            'g': 3
        }
    },
    'h': {
        'i': {
            'j': 2,
            'k': 4
        },
        'l': {
            'm': 5,
            'n': 6
        }
    }
}

value = 2
keys = get_keys_from_value(nested_dict, value)
print(keys)

['a.b.d', 'a.e.f', 'h.i.j']