self

What is `self` in Python?

Suppose you go to a family function... Everyone’s calling each other “beta”, “bhai”, “didi”...

But how do you know they’re talking about YOU?

That’s where self comes in.

In Python classes, self is like saying "me, this exact object."

🔹 What does `self` mean?

It refers to the current object of the class
Let’s you access that object’s own data and methods
It’s automatically passed in every method (you don’t have to pass it manually)

💡 Example

class BankAccount:
    def __init__(self, name, balance):
        self.name = name
        self.balance = balance

    def show_info(self):
        print(f"Account holder: {self.name}")
        print(f"Balance: {self.balance}")

Now if you create:

acc1 = BankAccount("Maham", 1000)
acc1.show_info()

Output:

Account holder: Maham  
Balance: 1000

🔍 Why did it print Maham?

Because:

acc1 is the object
self.name = acc1.name
So self = acc1 in this case

🧠 Why Not Just Use `name` Instead of `self.name`?

Without self, Python thinks name is just a local variable
With self.name, you’re saying → this belongs to the object itself

Like:

self.name = name

Left side → object variable
Right side → local input from constructor

🔄 Can We Name It Anything Else?

Technically yes. You can write:

def __init__(banana, name):
    banana.name = name

But please don’t.
Everyone in Python uses self. It's a standard.

🧪 When and Where to Use `self`

Use case	Need `self`?	Why
Set property in constructor	✅ Yes	Object-level variable
Access method inside class	✅ Yes	Belongs to the object
Call static/class method	❌ No	They don’t use object
Outside class?	❌ No	You use object name

🤔 Common Questions You May Have

Is self a keyword?
→ No. Just a naming convention (but must be first argument)
Do I always need to write self in methods?
→ Yes, in instance methods (normal methods)
Can I access self.property in another method?
→ Yes! That's the whole point of using self — so data stays with the object
What about class-level variables?
→ Those are accessed with ClassName.property or self.__class__.property

🚫 Don’t Confuse

Wrong	Why wrong	Fix it
`balance = 100` inside method	Local only, not saved	Use `self.balance = 100`
`print(name)` inside class	No such variable	Use `self.name`

🧶 Summary in One Line

self is how an object talks to itself.

Simple. Clean. Py-thonic.

Stay Connected - @syedamahamfahim 🐬