Protected variable in Python Last Updated : 10 Jan, 2020 Summarize Suggest changes Share Like Article Like Report Prerequisites: Underscore ( _ ) in Python A Variable is an identifier that we assign to a memory location which is used to hold values in a computer program. Variables are named locations of storage in the program. Based on access specification, variables can be public, protected and private in a class. Protected variables are those data members of a class that can be accessed within the class and the classes derived from that class. In Python, there is no existence of “Public” instance variables. However, we use underscore '_' symbol to determine the access control of a data member in a class. Any member prefixed with an underscore should be treated as a non-public part of the API or any Python code, whether it is a function, a method or a data member. Example 1: Python3 # program to illustrate protected # data members in a class # Defining a class class Geek: # protected data members _name = "R2J" _roll = 1706256 # public member function def displayNameAndRoll(self): # accessing protected data members print("Name: ", self._name) print("Roll: ", self._roll) # creating objects of the class obj = Geek() # calling public member # functions of the class obj.displayNameAndRoll() Output: Name: R2J Roll: 1706256 Example 2: During Inheritance Python3 # program to illustrate protected # data members in a class # super class class Shape: # constructor def __init__(self, length, breadth): self._length = length self._breadth = breadth # public member function def displaySides(self): # accessing protected data members print("Length: ", self._length) print("Breadth: ", self._breadth) # derived class class Rectangle(Shape): # constructor def __init__(self, length, breadth): # Calling the constructor of # Super class Shape.__init__(self, length, breadth) # public member function def calculateArea(self): # accessing protected data members of super class print("Area: ", self._length * self._breadth) # creating objects of the # derived class obj = Rectangle(80, 50) # calling derived member # functions of the class obj.displaySides() # calling public member # functions of the class obj.calculateArea() Output: Length: 80 Breadth: 50 Area: 4000 In the above example, the protected variables _length and _breadth of the super class Shape are accessed within the class by a member function displaySides() and can be accessed from class Rectangle which is derived from the Shape class. The member function calculateArea() of class Rectangle accesses the protected data members _length and _breadth of the super class Shape to calculate the area of the rectangle. Advertise with us Next Article Inheritance in Python R riturajsaha Follow Similar Reads Python OOPs Concepts Object Oriented Programming is a fundamental concept in Python, empowering developers to build modular, maintainable, and scalable applications. By understanding the core OOP principles (classes, objects, inheritance, encapsulation, polymorphism, and abstraction), programmers can leverage the full p 11 min read Python Classes and Objects A class in Python is a user-defined template for creating objects. It bundles data and functions together, making it easier to manage and use them. When we create a new class, we define a new type of object. 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In Python, destructors are not needed as much as in C++ because Python has a garbage collector that handles memory management automatically. The __del__() method is a known as a destructor method in Python. It is called when 7 min read 8 Tips For Object-Oriented Programming in PythonOOP or Object-Oriented Programming is a programming paradigm that organizes software design around data or objects and relies on the concept of classes and objects, rather than functions and logic. Object-oriented programming ensures code reusability and prevents Redundancy, and hence has become ver 6 min read Article Tags : Python python-oop-concepts Python-OOP Practice Tags : python Like