__getitem__ — Easy Examples

Enables indexing with square brackets (obj[key])

EasyIntermediateAdvancedExpert

Implementing __getitem__

Basic implementation of __getitem__ in a class.

python
class Matrix:
    def __init__(self, data):
        self.data = data

    def __getitem__(self, key):
        return self.data[key]

m = Matrix([[1, 2], [3, 4]])
print(m[0])
print(m[1][0])

__getitem__ enables indexing with square brackets (obj[key]). Implementing it lets you customize how Python interacts with your objects.

__getitem__ in action

Seeing __getitem__ called by Python's built-in operations.

python
# How Python calls __getitem__ automatically
class Demo:
    def __init__(self, value):
        self.value = value

    def __getitem__(self, other):
        print(f"__getitem__ was called!")
        return self

d = Demo(42)
# This triggers __getitem__:
print(d[0])

Python automatically calls __getitem__ when you use the corresponding operator or function on your object.

Want to try these examples interactively?

Open Easy Playground
Intermediate Examples →