TypeError：Dog（）不接受任何参数

Question

错误在哪里？我所做的一切与视频教程/书籍中的相同，没有出现错误。当然，也许还有另一个版本的python。我怎么了？

class Dog():
    """Simple dog model"""

    def _init_(self,name, age):
        """Initialize attributes, name and age"""
        self.name = name
        self.age = age
        """Dog created"""
        def sit(self):
            """The dog will sit down on command"""
            print(self.name.title()+ " the dog sat down")


        def jump():
            """The dog will jump on command"""
            print(self.name.title()+" the dog jumped")


my_dog = Dog()
print(my_dog.name)

我得到：

Traceback (most recent call last):
  File "C:/Users/Professional/PycharmProjects/thebasics/exmplclass.py", line 22, in <module>
    my_dog = Dog('topik',5)
TypeError: Dog() takes no arguments
Process finished with exit code 1