class Programer(object):
    hobby='Play Computer'

    def __init__(self, name, age, weight):
        self.name = name
        self._age = age
        self.__weight = weight
    
    @classmethod
    def get_hobby(cls):
        return cls.hobby

    @property
    def get_weight(self):
        return self.__weight

    def self_introduction(self):
        print ('My name is %s \nI an %s years old\n' %(self.name, self.age))

class BackendProgramer(Programer):
    def __int__(self, name, age, weight, language):
        super(BackendProgramer, self).__int__(name, age, weight)
        self.language = language

if __name__ == '__main__':
    programer = BackendProgramer.('Albert', 25, 80, 'Python')
    print (dir(programer))
    print (programer.__dir__)
    print (type(programer))
    print (isinstance(programer, Programer))

报错信息如下：

Traceback (most recent call last):

  File "C:/Users/WMY/Documents/python study/2017-2-12.py", line 26, in <module>

    programer = BackendProgramer('Albert', 25, 80, 'Python')

TypeError: __init__() takes 4 positional arguments but 5 were given

不懂啥意思，只有4个参数呀，求解？