20 - 如果列表元素是对象，该如何进行排序

class MyClass:
    def __init__(self):
        self.value = 0
      
    '''
    def __gt__(self, other):
        return self.value > other.value
        '''
    
    def __lt__(self, other):
        return self.value > other.value
        
    
my1 = MyClass()
my1.value = 20

my2 = MyClass()
my2.value = 10

my3 = MyClass()
my3.value = 30

a = [my1, my2, my3]
print(a)

import operator

# a.sort()

a.sort(key=operator.attrgetter('value'))
b = sorted(a, key=operator.attrgetter('value'))
print(a[0].value)
print(a[1].value)
print(a[2].value)

print(b[0].value)

[<__main__.MyClass object at 0x00000205D1AB5DA0>, <__main__.MyClass object at 0x00000205D1AB5668>, <__main__.MyClass object at 0x00000205D1AB5D68>]

10

20

30

10

# a.sort(key=operator.attrgetter('value'), reverse=True)

a.sort()

print(a[0].value)
print(a[1].value)
print(a[2].value)

30

20

10