在给定未知长度的“键路径”的情况下，将数据写入嵌套字典

def write_to_nested_dict(nested_dict, key_path, data):
    current_dict = nested_dict
    for key in key_path:
        if key not in current_dict:
            current_dict[key] = {}
        current_dict = current_dict[key]
    current_dict.update(data)

# 示例用法
nested_dict = {}
key_path = ['level1', 'level2', 'level3']
data = {'value': 42}
write_to_nested_dict(nested_dict, key_path, data)
print(nested_dict)

{'level1': {'level2': {'level3': {'value': 42}}}}