advanced

Introduction Abstraction is the process of hiding the real implementation of an application from the user and emphasizing only on usage of it. Abstraction in Python is achieved by using Abstract Base Classes (ABCs) 1. The abc module in Python library provides the infrastructure for defining custom abstract base classes. Abstract classes are classes that contain one or more abstract methods and generally provides incomplete functionality. An abstract method is a method that is declared, but contains no implementation....

Introduction A Metaclass means the class of a class. In Python Classes are objects, which are instances of some Class. As can see below every Class in Python are instance of a class type. class Example: pass >>> type(Example) <class 'type'> type is a MetaClass in Python which is responsible for classes creation. Dynamic Class creation using type() When type() is called with one argument, it returns the argument type....

Iterator Iterator is an object that can loop over iterable objects. We can use Iterator in for loops. A list is a well known Iterator. Implementaion An object can be a Iterator, if we implement two methods: __iter__ - returns the object itself. __next__ - returns the next values and raises StopIteration exception when all objects are looped. Generator Generator functions allow you to declare a function that behaves like an iterator....

Introduction Before looking into Decorators, we need to know key points about Functions in Python. Functions are Objects. Means they can be referenced, passed as an argument, can be returned as well. Decorators dynamically alter the functionality of a function, method, or class without having to directly use subclasses or change the source code of the function being decorated Implementaion Function as a Decorator Boilerplate Code: import functools def decorator(func): @functools....

Introduction Context managers allow you to allocate and release resources precisely when you want to. The most widely used example of context managers is the with statement. Suppose you have two related operations which you’d like to execute as a pair, with a block of code in between. Context managers allow you to do specifically that. Implementaion In the below example we will implement a program to open the file and read its contents using two methods....