Immutable

Immutable:

Once we create an object, we can not change in that object. If we try to change then with those changes a new object is created.

This non-changeable is called immutable.

When a object is created, Simple put, a mutable object can be data is changeable after it is created, and an immutable object can't. Objects of built-in types like (int, float, bool, str, tuple, unicode) are immutable. Objects of built-in types like (list, set, dict) are mutable. Custom classes are generally mutable.

Every object reference holds an object data(instance). When an object is created, it is assigned a unique object address(id). Its data type is defined at runtime and once set can never change, However its state can be changed if it is mutable. Simple put, a mutable object can be changed after it is created, and an immutable object can’t.

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