在具有重复键的字典(包含值数组)中查找值

def find_value_in_dict(dictionary, target_value):
    for key, value_array in dictionary.items():
        for value in value_array:
            if value == target_value:
                return key
    return "未找到目标值"

# 示例字典
my_dict = {
    "key1": [1, 2, 3],
    "key2": [4, 5, 6],
    "key3": [7, 8, 9]
}

# 查找值为5的键
result = find_value_in_dict(my_dict, 5)
print(result)  # 输出：key2