isinstance()

The isinstance() function in Python is a built-in function used to check if an object is an instance of a specified class. It takes two arguments - the object to be checked and the class or type as a second argument. It returns True if the object is an instance of the specified class, and False otherwise.

Parameter Values

Parameter Description
object

The object to be checked.
classinfo

A class, type, or tuple of classes and types to check against.

Return Values

The isinstance() function can return a bool, either True or False.

How to Use isinstance() in Python

Example 1:

The isinstance() function checks if an object is an instance of a specified class or any of its subclasses.

class Dog:
    breed = 'Poodle'

my_dog = Dog()
result = isinstance(my_dog, Dog)
print(result) # True
Example 2:

It can also accept a tuple of classes to check if the object is an instance of any of the specified classes.

class Car:
    brand = 'Toyota'

class Bicycle:
    type = 'Mountain'

my_vehicle = Car()
result = isinstance(my_vehicle, (Car, Bicycle))
print(result) # True
Example 3:

The isinstance() function is commonly used for type checking in Python to validate input parameters or determine the type of objects in a program.

def process_data(data):
    if not isinstance(data, (list, tuple)):
        raise ValueError('Data must be a list or tuple')
    
    for item in data:
        print(f'Processing: {item}')

Built-In Functions