在python中使用get attr求和值并忽略"None“值？

def sum_values(obj):
    total = 0
    for attr in dir(obj):
        value = getattr(obj, attr)
        if value is not None:
            total += value
    return total

class MyClass:
    def __init__(self):
        self.attr1 = 10
        self.attr2 = None
        self.attr3 = 5

obj = MyClass()
result = sum_values(obj)
print(result)  # 输出 15