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

I want to develop website which uses rest-api and Inventory/stock functionality in Python-Django. From where should I start
It seems you want to work on Django Web Framework. The very first pre-requisite for this is that you must know Python Programming. So, I would say learn Python first before embarking on Django Web-Framework.
Sourav
0 0
9

Hi   i am vishnu. I did my Post  Diploma in Tool design after DME and am now working in an MNC as contract base which will be completed on April 2020. Now i am in search of a job and i want to know any other courses like PYTHON or SAP which is best as i am not having any job opportunities in my domain. Please suggest a course and tell me whether I can do it or not as I only hold a Diploma degree 

Thankyou 
First of all, most of the companies have criteria for graduate or equivalent.2nd, if you want to go with SAP, it requires at least 1-2 years experience to get you a job. You get a job in a particular domain...
Vishnu Sai
Hi, I'm BCA graduate, and I have seven years in the general insurance field now I want to change my profile and upgrade my knowledge. Will learning python help me with my growth in my career?
Hi, as far as my knowledge goes first, you should learn data processing tools or programs like MS Excel, Power Bi, or SQL then you should then take a leap into Python, which will make automating your work quite simple.
Supriya
Why still in India lot of people are learning Java and .Net etc. We know that Python is in very demand in now-a-days. Recently I came to know that infosys and wipro was not able to undertake a project because it need to be develop in Python (source economictimes). What may be the good way to have a awareness about Python Language?
Let me contradict and clarify. firstly, Python is built on C API or C routines. Hence, the argument that scalability and reliability are the issues with Python is totally wrong. Secondly, Python is natively...
Vikas kumar
I want to learn Python in a month. Please help me for this.
Hi Gourab. I teach Python from basic level to advanced topics ---- teach them online. If you are interested , please contact me. I have a total IT experience of over 28 years and a regular Corporate and Individual Trainer.
Gourab

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

Ask a Question

Related Lessons

Machine Learning With Python
1. Course description: Machine Learning with Python has been designed for the provision of having strong hold in creating Machine learning algorithms with the base of Python. This has been preferred as...
J

Johnnie Clark

0 0
0
Nested Loops And Pattern In Python

Akash Roy

0 0
0
Python Overview
Python is a high-level, interpreted, interactive and object-oriented scripting language. Python was developed by Gudo vanRossum in the late eighties and early nineties at the National Research Institute...

Aruna M.

0 0
0
Python Data Science

Khadeer Pasha

0 0
0
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

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 Jaipur
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