查找与嵌套字典中的某个值匹配的所有键，并使用这些值作为键创建一个新字典

def find_keys(dictionary, value):
    keys = []
    for k, v in dictionary.items():
        if v == value:
            keys.append(k)
        elif isinstance(v, dict):
            subkeys = find_keys(v, value)
            for subkey in subkeys:
                keys.append(f"{k}.{subkey}")
    return keys

# 定义一个嵌套字典
nested_dict = {
    'a': 1,
    'b': {
        'c': 2,
        'd': {
            'e': 3,
            'f': 4
        },
        'g': 2
    },
    'h': 2
}

# 查找值为2的所有键
matching_keys = find_keys(nested_dict, 2)
print(matching_keys)

['b.c', 'b.d.e', 'b.g', 'h']