self_class_instance.md

self (class instance)

When implementing the class, regardless of whether it is __init__ or any other method, you can often see self appear in the parameter. What exactly is self?

Table of Contents

• self (class instance)
  • Table of Contents
  • Basic

Basic

Simply put, self stands for the "object" who was created to take advantage of this class, the instance itself.

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age
        print(self)   # <__main__.Person object at 0x000001F5DBCB8708>


p = Person("Jay", 20)
print(p)              # <__main__.Person object at 0x000001F5DBCB8708>

So when your class has a function with an instance, you can use a function with class and pass an instance into it.

class Person:
    def say(self):
        print('Hello')


p = Person()
Person.say(p)  # Exactly the same as `p.say()`

There is no meaning, but python accepts it.