如何根据attr数组的内容查找类实例？

class MyClass:
    def __init__(self, attr1, attr2, attr3):
        self.attr1 = attr1
        self.attr2 = attr2
        self.attr3 = attr3

# 示例类实例数组
instances = [
    MyClass("value1", "value2", "value3"),
    MyClass("value4", "value5", "value6"),
    MyClass("value7", "value8", "value9")
]

# 给定的attr数组
attr = ["value4", "value5", "value6"]

# 存储匹配结果的数组
result = []

# 遍历类实例数组
for instance in instances:
    # 获取类实例的属性列表
    instance_attrs = [instance.attr1, instance.attr2, instance.attr3]
    
    # 判断属性列表与attr数组是否完全匹配
    if instance_attrs == attr:
        result.append(instance)
    # 判断属性列表与attr数组是否部分匹配
    elif all(a == b or b is None for a, b in zip(instance_attrs, attr)):
        result.append(instance)

# 输出匹配结果
for instance in result:
    print(instance)