In this article, we will learn inheritance and extending classes in Python 3.x. Or earlier.
Inheritance represents real-world relationships well, provides reusability & supports transitivity. It offers faster development time, easier maintenance and easy to extend.
Inheritance is broadly categorized into 5 types −
- Single
- Multiple
- Hierarchical
- Multi-level
- Hybrid
As shown in the figure above that inheritance is the process in which we try to access the features of other classes without actually making the object of the parent class.
Here we will be learning about the implementation of single and Hierarchical inheritances.
Single inheritance
Example
# parent class
class Student():
# constructor of parent class
def __init__(self, name, enrollnumber):
self.name = name
self.enrollnumber = enrollnumber
def display(self):
print(self.name)
print(self.enrollnumber)
# child class
class College( Student ):
def __init__(self, name, enrollnumber, admnyear, branch):
self.admnyear = admnyear
self.branch = branch
# invoking the __init__ of the parent class
Student.__init__(self, name, enrollnumber)
# creation of an object for base/derived class
obj = College('Rohit',42414802718,2018,"CSE")
obj.display()Output
Rohit 42414802718
Multiple inheritance
Example
# parent class
class Student():
# constructor of parent class
def __init__(self, name, enrollnumber):
self.name = name
self.enrollnumber = enrollnumber
def display(self):
print(self.name)
print(self.enrollnumber)
# child class
class College( Student ):
def __init__(self, name, enrollnumber, admnyear, branch):
self.admnyear = admnyear
self.branch = branch
# invoking the __init__ of the parent class
Student.__init__(self, name, enrollnumber)
# child class
class University( Student ):
def __init__(self, name, enrollnumber, refno, branch):
self.refno = refno
self.branch = branch
# invoking the __init__ of the parent class
Student.__init__(self, name, enrollnumber)
# creation of an object for base/derived class
obj_1 = College('Rohit',42414802718,2018,"CSE")
obj_1.display()
obj_2 = University ('Rohit',42414802718,"st2018","CSE")
obj_2.display()Output
Rohit 42414802718 Rohit 42414802718
Conclusion
In this article, we learned about Inheritance in Python broadly single and hierarchical inheritance.