Python __init__() - Working and Examples

Python init()

__init__() is a builtin function in Python, that is called whenever an object is created. __init__() initializes the state for the object. Meaning, it is a place where we can set the attributes of an object.

We can also pass arguments to __init__() function, so that each object when created, can be created as unique.

If __init__() function is not defined in a class, there will be an implicit call to the inbuilt __init__() function.

Simple Example for __init__() in Python

In the following example, we have defined a class with __init__() function, where we will initialize some of the object parameters.

Python Program

class Laptop:
	
	def __init__(self, name, processor, hdd, ram, cost):
		self.name = name
		self.processor = processor
		self.hdd = hdd
		self.ram = ram
		self.cost = cost
		
	def details(self):
		print('The details of the laptop are:')
		print('Name         :', self.name)
		print('Processor    :', self.processor)
		print('HDD Capacity :', self.hdd)
		print('RAM          :', self.ram)
		print('Cost($)      :', self.cost)
		
#create object
laptop1 = Laptop('Dell Alienware', 'Intel Core i7', 512, 8, 2500.00)

print(laptop1.name)
print(laptop1.processor)

laptop1.details()

Output

Dell Alienware
Intel Core i7
The details of the laptop are:
Name         : Dell Alienware
Processor    : Intel Core i7
HDD Capacity : 512
RAM          : 8
Cost($)      : 2500.0

You can see that we have done lot of things with the class object. We will look deeper into those aspects.

• __init__() function initialized parameters, with the values passed as arguments to it.
• The declaration part of parameters for the class has been done inside the __init__() function.
• The parameters can be accessed in other methods of the class and also with the object reference.

Summary

In this tutorial of Python Examples, we learned about __init__, how to use __init__ in a class definition, and how to override inbuilt __init__() function of a class in Python.