Identity Operators in Python

Python Identity Operators

Python identity operators are used to compare the memory locations of objects rather than their values. This means that identity operators check whether two variables point to the same object in memory, which is crucial in understanding how Python manages data and memory. In this lesson, we will cover the two primary identity operators: is and is not.

1. Identity Operator: is

The is operator returns True if both variables refer to the same object in memory. If the variables point to different objects, it returns False.

Syntax:

1
x is y

Example:

1
2
3
a = [1, 2, 3]
b = a
result = (a is b)  # result will be True because both variables point to the same list object.

Practical Use:

Use the is operator when you need to check if two variables reference the same object. This is particularly useful when working with mutable objects like lists and dictionaries, where changes to one variable can affect the other if they reference the same object.

2. Identity Operator: is not

The is not operator returns True if both variables do not refer to the same object. If they do point to the same object, it returns False.

Syntax:

1
x is not y

Example:

1
2
3
a = [1, 2, 3]
b = [1, 2, 3]
result = (a is not b)  # result will be True because they are different objects in memory.

Practical Use:

Use the is not operator when you need to check that two variables do not reference the same object. This can help you avoid unintentional modifications when working with mutable data types.