What is __contains__() in Python?

Asked by Last Modified  

3 Answers

Learn Python

Follow 2
Answer

Please enter your answer

Mohit Gauniyal

Empowering Python learners with practical expertise.

__contains__() is a special method in Python that allows an object to define its own behavior when it is checked for containment in another object using the in keyword. The method should return True if the object contains the given value, and False otherwise. Here's an example that demonstrates how...
read more
__contains__() is a special method in Python that allows an object to define its own behavior when it is checked for containment in another object using the in keyword. The method should return True if the object contains the given value, and False otherwise. Here's an example that demonstrates how to use __contains__(): class MyList: def __init__(self, values): self.values = values def __contains__(self, value): return value in self.values my_list = MyList([1, 2, 3, 4, 5]) print(3 in my_list) # output: Trueprint(6 in my_list) # output: False In this example, the MyList class defines its own behavior for the in keyword by implementing the __contains__() method. The method simply checks whether the given value is in the values list and returns True or False accordingly. Note that __contains__() can be implemented for any custom object type in Python, and is often used for container types such as lists, sets, and dictionaries. read less
Comments
Dislike Bookmark

Research Engineer with 20+years experience

__contains__() is a special method in Python that allows objects to define custom behavior for the in operator. The in operator is used to test if a value is a member of a sequence or a collection. When an object defines the __contains__() method, it can be used with the in operator to determine if...
read more
__contains__() is a special method in Python that allows objects to define custom behavior for the in operator. The in operator is used to test if a value is a member of a sequence or a collection. When an object defines the __contains__() method, it can be used with the in operator to determine if a given value is contained within the object. The __contains__() method should return True if the value is present in the object, and False otherwise. Here's an example of how __contains__() can be used: class MyList: def __init__(self, data): self.data = data def __contains__(self, value): return value in self.data my_list = MyList([1, 2, 3, 4, 5]) print(3 in my_list) # Output: Trueprint(6 in my_list) # Output: False read less
Comments
Dislike Bookmark

IT Professional Trainer with 14 years of Experience

In Python, the __contains__() method is a special method that allows objects to define their own behavior when used with the in operator. It is called by the in operator to check if a given value is present in the object. The __contains__() method takes two parameters: self (representing the object...
read more
In Python, the __contains__() method is a special method that allows objects to define their own behavior when used with the in operator. It is called by the in operator to check if a given value is present in the object. The __contains__() method takes two parameters: self (representing the object itself) and item (representing the value being checked). It should return True if the item is found in the object, and False otherwise. Here's an example to illustrate the usage of __contains__() method: class MyList: def __init__(self, items): self.items = items def __contains__(self, item): return item in self.items my_list = MyList([1, 2, 3, 4, 5]) print(3 in my_list) # Output: Trueprint(6 in my_list) # Output: False In this example, we define a custom class MyList that wraps a list of items. The __contains__() method is implemented to check if an item is present in the list by using the in operator on the self.items attribute. By implementing the __contains__() method, objects of the MyList class can now be used with the in operator to check for membership of a specific value in the list. Note that if the __contains__() method is not defined for an object, Python falls back to other methods to determine the containment. For example, it checks if the object has an __iter__() method and uses it to iterate over the elements, or it checks if the object has a __getitem__() method to access the elements by index. read less
Comments
Dislike Bookmark

View 1 more Answers

Related Questions

which is best in Rpa and python
Python is much preferrable, I would suggest you to go for Python. As it is now a days used in Automations too.
K
How do I learn Python?
Start with online tutorials, books, and practice coding. Join communities and work on projects to improve.
Kirti
0 0
6
Is there any online Python coaching classes available?
Yes it is. You can contact me and visit my profile for Online classes
Abhishek
0 0
5
Is it required to know (pre-requisite) Python to learn iron python?
No not required.
Chaitanya
0 0
7
Is learning Python good or bad?
Its depend on your requirement, I mean if you are seeking for good opportunity to move from one Org. to another, or migrating some applications into your project, or your manager are eagerly requesting...
Harish
0 0
7

Now ask question in any of the 1000+ Categories, and get Answers from Tutors and Trainers on UrbanPro.com

Ask a Question

Related Lessons

Decorator in Python - Simplified
By definition, a decorator is a function that takes another function andextends(/decorates) the behaviour of the latter function without explicitly modifying it.Let see how we can apply decorators for...

Logeswaran

0 0
0
How to know if an object is iterable?
An object in python is said to be an iterable if it obeys one of the following two rules:- 1. Object must consist of __getitem__ method 2. Object must consist of __iter__ method. String objects generally...
S

Sudheer S

0 0
0
Learn Python : Formatting with the .format () method
A good way to format objects into your strings for print statements is with the string.format() method. The syntax is :'String here {} then also {}'.format('something1','something2')Example 1:print("This...
B

Biswanath Banerjee

0 1
0
Benefits of Design Patterns in Application Development
Application developments is a tedious job. Programmers write code and test it again and again to make sure their software works fine. So designing complex software is a hard nut to crack. Skilled programmers...

Shibaji Debnath

2 0
0
Python Script for random Password generation
from random import randintdef passwordgen(request): str_not_include = "1 L I i l o O 0" str_small ="abcdefghjkmnpqrstuvwxyz" str_caps = str_small.upper() str_num = "23456789" str_special...

Mohommed Iqbal Hawre

0 0
0

Recommended Articles

Top 5 reasons why you should learn Python

Python is one of the most popular programming languages in the world. It is general-purpose, object oriented, high-level programming language used in a number of programming fields. Python is a great programming language to learn as it will introduce you to the world of programming. If you are from the technical background...

Read full article >

Why Should you Become an IT Consultant

Information technology consultancy or Information technology consulting is a specialized field in which one can set their focus on providing advisory services to business firms on finding ways to use innovations in information technology to further their business and meet the objectives of the business. Not only does...

Read full article >

What is Applications Engineering all about?

Applications engineering is a hot trend in the current IT market.  An applications engineer is responsible for designing and application of technology products relating to various aspects of computing. To accomplish this, he/she has to work collaboratively with the company’s manufacturing, marketing, sales, and customer...

Read full article >

Learn Microsoft Excel

Microsoft Excel is an electronic spreadsheet tool which is commonly used for financial and statistical data processing. It has been developed by Microsoft and forms a major component of the widely used Microsoft Office. From individual users to the top IT companies, Excel is used worldwide. Excel is one of the most important...

Read full article >

Find Python Training classes near you
Python Training classes in Bangalore
Python Training classes in Hyderabad
Python Training classes in Chennai
Python Training classes in Delhi
Python Training classes in Pune
Python Training classes in Mumbai
Python Training classes in Noida
Python Training classes in Kolkata
Python Training classes in Gurgaon
Python Training classes in Ghaziabad
Online Python Training

Looking for Python Training classes?

Learn from the Best Tutors on UrbanPro

Are you a Tutor or Training Institute?

Join UrbanPro Today to find students near you