python set()去重的底层原理及实例

ls = [1,2,3,1,2]
print(set(ls))

class Foo:
    def __init__(self,name,count):
        self.name = name
        self.count = count
    def __hash__(self):
        print("%s调用了哈希方法"%self.name)
        return hash(id(self))
    def __eq__(self, other):
        print("%s调用了eq方法")
        if self.__dict__ == other.__dict__:
            return True
        else:return False
f1 = Foo('f1',1)
f2 = Foo('f2',2)
f3 = Foo('f3',3)
ls = [f1,f2,f3]
print(set(ls))

class Foo:
    def __init__(self,name,count):
        self.name = name
        self.count = count
    def __hash__(self):
        print("%s调用了哈希方法"%self.name)
        return hash(self.count)
    def __eq__(self, other):
        print("%s调用了eq方法"%self.name)
        return self.__dict__ == other.__dict__
f1 = Foo('f1',1)
f2 = Foo('f2',1)
f3 = Foo('f3',3)
ls = [f1,f2,f3]
print(set(ls))

f1 = Foo('f1',1)
f2 = Foo('f1',1)
f3 = Foo('f3',3)
ls = [f1,f2,f3]
print(set(ls))

class Staff:
    def __init__(self,name,gender,age,department):
        self.name = name
        self.gender = gender
        self.age  = age
        self.department = department
    def __hash__(self):
        return hash(self.name+self.gender)
    def __eq__(self, other):
        return True
ls = ['zs','ls','ww','zq']
gender_list = ['man','femal']
staff_list = []
for i in range(100):
    staff_list.append(Staff(ls[i%4],gender_list[i%2],i,'class'))
print(set(staff_list))
print([(i.name,i.gender) for i in set(staff_list)])