- Blog Categories
- Software Development Projects and Ideas
- 12 Computer Science Project Ideas
- 28 Beginner Software Projects
- Top 10 Engineering Project Ideas
- Top 10 Easy Final Year Projects
- Top 10 Mini Projects for Engineers
- 25 Best Django Project Ideas
- Top 20 MERN Stack Project Ideas
- Top 12 Real Time Projects
- Top 6 Major CSE Projects
- 12 Robotics Projects for All Levels
- Java Programming Concepts
- Abstract Class in Java and Methods
- Constructor Overloading in Java
- StringBuffer vs StringBuilder
- Java Identifiers: Syntax & Examples
- Types of Variables in Java Explained
- Composition in Java: Examples
- Append in Java: Implementation
- Loose Coupling vs Tight Coupling
- Integrity Constraints in DBMS
- Different Types of Operators Explained
- Career and Interview Preparation in IT
- Top 14 IT Courses for Jobs
- Top 20 Highest Paying Languages
- 23 Top CS Interview Q&A
- Best IT Jobs without Coding
- Software Engineer Salary in India
- 44 Agile Methodology Interview Q&A
- 10 Software Engineering Challenges
- Top 15 Tech's Daily Life Impact
- 10 Best Backends for React
- Cloud Computing Reference Models
- Web Development and Security
- Find Installed NPM Version
- Install Specific NPM Package Version
- Make API Calls in Angular
- Install Bootstrap in Angular
- Use Axios in React: Guide
- StrictMode in React: Usage
- 75 Cyber Security Research Topics
- Top 7 Languages for Ethical Hacking
- Top 20 Docker Commands
- Advantages of OOP
- Data Science Projects and Applications
- 42 Python Project Ideas for Beginners
- 13 Data Science Project Ideas
- 13 Data Structure Project Ideas
- 12 Real-World Python Applications
- Python Banking Project
- Data Science Course Eligibility
- Association Rule Mining Overview
- Cluster Analysis in Data Mining
- Classification in Data Mining
- KDD Process in Data Mining
- Data Structures and Algorithms
- Binary Tree Types Explained
- Binary Search Algorithm
- Sorting in Data Structure
- Binary Tree in Data Structure
- Binary Tree vs Binary Search Tree
- Recursion in Data Structure
- Data Structure Search Methods: Explained
- Binary Tree Interview Q&A
- Linear vs Binary Search
- Priority Queue Overview
- Python Programming and Tools
- Top 30 Python Pattern Programs
- List vs Tuple
- Python Free Online Course
- Method Overriding in Python
- Top 21 Python Developer Skills
- Reverse a Number in Python
- Switch Case Functions in Python
- Info Retrieval System Overview
- Reverse a Number in Python
- Real-World Python Applications
- Data Science Careers and Comparisons
- Data Analyst Salary in India
- Data Scientist Salary in India
- Free Excel Certification Course
- Actuary Salary in India
- Data Analyst Interview Guide
- Pandas Interview Guide
- Tableau Filters Explained
- Data Mining Techniques Overview
- Data Analytics Lifecycle Phases
- Data Science Vs Analytics Comparison
- Artificial Intelligence and Machine Learning Projects
- Exciting IoT Project Ideas
- 16 Exciting AI Project Ideas
- 45+ Interesting ML Project Ideas
- Exciting Deep Learning Projects
- 12 Intriguing Linear Regression Projects
- 13 Neural Network Projects
- 5 Exciting Image Processing Projects
- Top 8 Thrilling AWS Projects
- 12 Engaging AI Projects in Python
- NLP Projects for Beginners
- Concepts and Algorithms in AIML
- Basic CNN Architecture Explained
- 6 Types of Regression Models
- Data Preprocessing Steps
- Bagging vs Boosting in ML
- Multinomial Naive Bayes Overview
- Gini Index for Decision Trees
- Bayesian Network Example
- Bayes Theorem Guide
- Top 10 Dimensionality Reduction Techniques
- Neural Network Step-by-Step Guide
- Technical Guides and Comparisons
- Make a Chatbot in Python
- Compute Square Roots in Python
- Permutation vs Combination
- Image Segmentation Techniques
- Generative AI vs Traditional AI
- AI vs Human Intelligence
- Random Forest vs Decision Tree
- Neural Network Overview
- Perceptron Learning Algorithm
- Selection Sort Algorithm
- Career and Practical Applications in AIML
- AI Salary in India Overview
- Biological Neural Network Basics
- Top 10 AI Challenges
- Production System in AI
- Top 8 Raspberry Pi Alternatives
- Top 8 Open Source Projects
- 14 Raspberry Pi Project Ideas
- 15 MATLAB Project Ideas
- Top 10 Python NLP Libraries
- Naive Bayes Explained
- Digital Marketing Projects and Strategies
- 10 Best Digital Marketing Projects
- 17 Fun Social Media Projects
- Top 6 SEO Project Ideas
- Digital Marketing Case Studies
- Coca-Cola Marketing Strategy
- Nestle Marketing Strategy Analysis
- Zomato Marketing Strategy
- Monetize Instagram Guide
- Become a Successful Instagram Influencer
- 8 Best Lead Generation Techniques
- Digital Marketing Careers and Salaries
- Digital Marketing Salary in India
- Top 10 Highest Paying Marketing Jobs
- Highest Paying Digital Marketing Jobs
- SEO Salary in India
- Brand Manager Salary in India
- Content Writer Salary Guide
- Digital Marketing Executive Roles
- Career in Digital Marketing Guide
- Future of Digital Marketing
- MBA in Digital Marketing Overview
- Digital Marketing Techniques and Channels
- 9 Types of Digital Marketing Channels
- Top 10 Benefits of Marketing Branding
- 100 Best YouTube Channel Ideas
- YouTube Earnings in India
- 7 Reasons to Study Digital Marketing
- Top 10 Digital Marketing Objectives
- 10 Best Digital Marketing Blogs
- Top 5 Industries Using Digital Marketing
- Growth of Digital Marketing in India
- Top Career Options in Marketing
- Interview Preparation and Skills
- 73 Google Analytics Interview Q&A
- 56 Social Media Marketing Q&A
- 78 Google AdWords Interview Q&A
- Top 133 SEO Interview Q&A
- 27+ Digital Marketing Q&A
- Digital Marketing Free Course
- Top 9 Skills for PPC Analysts
- Movies with Successful Social Media Campaigns
- Marketing Communication Steps
- Top 10 Reasons to Be an Affiliate Marketer
- Career Options and Paths
- Top 25 Highest Paying Jobs India
- Top 25 Highest Paying Jobs World
- Top 10 Highest Paid Commerce Job
- Career Options After 12th Arts
- Top 7 Commerce Courses Without Maths
- Top 7 Career Options After PCB
- Best Career Options for Commerce
- Career Options After 12th CS
- Top 10 Career Options After 10th
- 8 Best Career Options After BA
- Projects and Academic Pursuits
- 17 Exciting Final Year Projects
- Top 12 Commerce Project Topics
- Top 13 BCA Project Ideas
- Career Options After 12th Science
- Top 15 CS Jobs in India
- 12 Best Career Options After M.Com
- 9 Best Career Options After B.Sc
- 7 Best Career Options After BCA
- 22 Best Career Options After MCA
- 16 Top Career Options After CE
- Courses and Certifications
- 10 Best Job-Oriented Courses
- Best Online Computer Courses
- Top 15 Trending Online Courses
- Top 19 High Salary Certificate Courses
- 21 Best Programming Courses for Jobs
- What is SGPA? Convert to CGPA
- GPA to Percentage Calculator
- Highest Salary Engineering Stream
- 15 Top Career Options After Engineering
- 6 Top Career Options After BBA
- Job Market and Interview Preparation
- Why Should You Be Hired: 5 Answers
- Top 10 Future Career Options
- Top 15 Highest Paid IT Jobs India
- 5 Common Guesstimate Interview Q&A
- Average CEO Salary: Top Paid CEOs
- Career Options in Political Science
- Top 15 Highest Paying Non-IT Jobs
- Cover Letter Examples for Jobs
- Top 5 Highest Paying Freelance Jobs
- Top 10 Highest Paying Companies India
- Career Options and Paths After MBA
- 20 Best Careers After B.Com
- Career Options After MBA Marketing
- Top 14 Careers After MBA In HR
- Top 10 Highest Paying HR Jobs India
- How to Become an Investment Banker
- Career Options After MBA - High Paying
- Scope of MBA in Operations Management
- Best MBA for Working Professionals India
- MBA After BA - Is It Right For You?
- Best Online MBA Courses India
- MBA Project Ideas and Topics
- 11 Exciting MBA HR Project Ideas
- Top 15 MBA Project Ideas
- 18 Exciting MBA Marketing Projects
- MBA Project Ideas: Consumer Behavior
- What is Brand Management?
- What is Holistic Marketing?
- What is Green Marketing?
- Intro to Organizational Behavior Model
- Tech Skills Every MBA Should Learn
- Most Demanding Short Term Courses MBA
- MBA Salary, Resume, and Skills
- MBA Salary in India
- HR Salary in India
- Investment Banker Salary India
- MBA Resume Samples
- Sample SOP for MBA
- Sample SOP for Internship
- 7 Ways MBA Helps Your Career
- Must-have Skills in Sales Career
- 8 Skills MBA Helps You Improve
- Top 20+ SAP FICO Interview Q&A
- MBA Specializations and Comparative Guides
- Why MBA After B.Tech? 5 Reasons
- How to Answer 'Why MBA After Engineering?'
- Why MBA in Finance
- MBA After BSc: 10 Reasons
- Which MBA Specialization to choose?
- Top 10 MBA Specializations
- MBA vs Masters: Which to Choose?
- Benefits of MBA After CA
- 5 Steps to Management Consultant
- 37 Must-Read HR Interview Q&A
- Fundamentals and Theories of Management
- What is Management? Objectives & Functions
- Nature and Scope of Management
- Decision Making in Management
- Management Process: Definition & Functions
- Importance of Management
- What are Motivation Theories?
- Tools of Financial Statement Analysis
- Negotiation Skills: Definition & Benefits
- Career Development in HRM
- Top 20 Must-Have HRM Policies
- Project and Supply Chain Management
- Top 20 Project Management Case Studies
- 10 Innovative Supply Chain Projects
- Latest Management Project Topics
- 10 Project Management Project Ideas
- 6 Types of Supply Chain Models
- Top 10 Advantages of SCM
- Top 10 Supply Chain Books
- What is Project Description?
- Top 10 Project Management Companies
- Best Project Management Courses Online
- Salaries and Career Paths in Management
- Project Manager Salary in India
- Average Product Manager Salary India
- Supply Chain Management Salary India
- Salary After BBA in India
- PGDM Salary in India
- Top 7 Career Options in Management
- CSPO Certification Cost
- Why Choose Product Management?
- Product Management in Pharma
- Product Design in Operations Management
- Industry-Specific Management and Case Studies
- Amazon Business Case Study
- Service Delivery Manager Job
- Product Management Examples
- Product Management in Automobiles
- Product Management in Banking
- Sample SOP for Business Management
- Video Game Design Components
- Top 5 Business Courses India
- Free Management Online Course
- SCM Interview Q&A
- Fundamentals and Types of Law
- Acceptance in Contract Law
- Offer in Contract Law
- 9 Types of Evidence
- Types of Law in India
- Introduction to Contract Law
- Negotiable Instrument Act
- Corporate Tax Basics
- Intellectual Property Law
- Workmen Compensation Explained
- Lawyer vs Advocate Difference
- Law Education and Courses
- LLM Subjects & Syllabus
- Corporate Law Subjects
- LLM Course Duration
- Top 10 Online LLM Courses
- Online LLM Degree
- Step-by-Step Guide to Studying Law
- Top 5 Law Books to Read
- Why Legal Studies?
- Pursuing a Career in Law
- How to Become Lawyer in India
- Career Options and Salaries in Law
- Career Options in Law India
- Corporate Lawyer Salary India
- How To Become a Corporate Lawyer
- Career in Law: Starting, Salary
- Career Opportunities: Corporate Law
- Business Lawyer: Role & Salary Info
- Average Lawyer Salary India
- Top Career Options for Lawyers
- Types of Lawyers in India
- Steps to Become SC Lawyer in India
- Tutorials
- C Tutorials
- Recursion in C: Fibonacci Series
- Checking String Palindromes in C
- Prime Number Program in C
- Implementing Square Root in C
- Matrix Multiplication in C
- Understanding Double Data Type
- Factorial of a Number in C
- Structure of a C Program
- Building a Calculator Program in C
- Compiling C Programs on Linux
- Java Tutorials
- Handling String Input in Java
- Determining Even and Odd Numbers
- Prime Number Checker
- Sorting a String
- User-Defined Exceptions
- Understanding the Thread Life Cycle
- Swapping Two Numbers
- Using Final Classes
- Area of a Triangle
- Skills
- Software Engineering
- JavaScript
- Data Structure
- React.js
- Core Java
- Node.js
- Blockchain
- SQL
- Full stack development
- Devops
- NFT
- BigData
- Cyber Security
- Cloud Computing
- Database Design with MySQL
- Cryptocurrency
- Python
- Digital Marketings
- Advertising
- Influencer Marketing
- Search Engine Optimization
- Performance Marketing
- Search Engine Marketing
- Email Marketing
- Content Marketing
- Social Media Marketing
- Display Advertising
- Marketing Analytics
- Web Analytics
- Affiliate Marketing
- MBA
- MBA in Finance
- MBA in HR
- MBA in Marketing
- MBA in Business Analytics
- MBA in Operations Management
- MBA in International Business
- MBA in Information Technology
- MBA in Healthcare Management
- MBA In General Management
- MBA in Agriculture
- MBA in Supply Chain Management
- MBA in Entrepreneurship
- MBA in Project Management
- Management Program
- Consumer Behaviour
- Supply Chain Management
- Financial Analytics
- Introduction to Fintech
- Introduction to HR Analytics
- Fundamentals of Communication
- Art of Effective Communication
- Introduction to Research Methodology
- Mastering Sales Technique
- Business Communication
- Fundamentals of Journalism
- Economics Masterclass
- Free Courses
Identifiers in Python: Naming Rules & Best Practices
Updated on 18 November, 2024
14.58K+ views
• 7 min read
Table of Contents
- What are Identifiers?
- What are Keywords? How are they different from Identifiers?
- Naming rules for Identifiers in Python: How are Identifiers named?
- Valid Python Identifiers (Examples)
- Invalid Python Identifiers (Examples)
- How to check the validity of Identifier names?
- What are the best practices for Naming Identifiers in Python?
- Conclusion
Python is an object-oriented high-level programming language that has been widely accepted for general-purpose programming. Built by the Python Software Foundation in 1991, it has found its way into industrial-level programming and is currently the #3 most used programming language globally. As per Statista, nearly 48.24% of developers rely on Python to achieve desirable results in data science, making the language one of the most highly desirable data science skills for job seekers, apart from R and SQL.
The internet is flooded with courses that teach Python within months. Due to the rules mentioned above, the rapid growth of internet learning is flooded with courses on Python, which are now available to a broader audience across all age groups.
Like all programming languages, Python too has its attributes and rules that need to be followed when creating software applications. This article will discuss identifiers in Python and explore the rules and best practices for naming identifiers.
What are Identifiers?
Different programming elements need to be identified and named uniquely to differentiate them from others of the same kind. These are referred to as Identifiers. The user defines these names according to their choice and requirements. These include names for classes, functions, variables, methods, and so on.
For Python, identifiers work similarly, except for a few naming conventions that are unique to the language.
For example, Python doesn’t approve special characters such as @,%,$, etc., and punctuation marks within identifier names.
Also, identifier names cannot be the same as keywords.
What are Keywords? How are they different from Identifiers?
Reserved words in Python which cannot be used as an identifier like function names or variable names are known as keywords. They are helpful in the definition of the structure and syntax of Python. As of Python 3.7, there are 33 keywords. This number may increase or decrease over time. Except ‘True’, ‘False’, and ‘None’, all other keywords are found in lowercase and need to be used accordingly, keeping the case sensitivity in mind.
Naming rules for Identifiers in Python: How are Identifiers named?
For naming identifiers, Python has a unique set of rules that need to be followed. Here’s taking a look:
- Identifier names in Python can contain numbers (0-9), uppercase letters (A-Z), lowercase letters (a-z), and underscore (_).
- The name should always start with a non-numeric character.
- An identifier name should not contain numeric characters only.
- Identifier names in Python are case-sensitive like most other languages. (‘Ash’ is different from ‘ASH’).
- Users can begin identifiers with an underscore; it will not display an error.
- An identifier name can be of any length, although the PEP-8 standard rule advises limiting the number of characters in a line to 79.
- Identifiers should not carry the same name as keywords. (To avoid errors in this regard, users can type help() followed by “keywords” to view a list of all the keywords in Python.)
- Leading double underscores (__$) cannot be used as these category names are used for the context of the definition of a class. These are private variables of derived and base classes.
Deviation from any of these rules mentioned above may lead to error reports and cause runtime issues in the program:
Check out all trending Python tutorial concepts in 2024
Valid Python Identifiers (Examples)
Any combination of numbers, letters, and underscores which comply with the mentioned rules are accepted as valid Python identifiers. Some examples are:
- _pratt: identifier names can start with an underscore.
- _: this may look odd, but a single underscore can be used as an identifier name.
- alpha123: identifier names can begin with alphabets in lowercase.
- DoGs: identifier names can contain uppercase and lowercase alphabets in any pattern.
- DRE, dre, and Dre will be considered three different identifier names due to the difference in the case.
Invalid Python Identifiers (Examples)
Many identifier names that may be valid in other programming languages are invalid in the case of Python. Some examples are:
- 999: identify names that cannot contain only digits or numeric values.
- x+iy: identifier names cannot contain any other special character except underscore.
- While: identifier names cannot be reserved keywords that have separate meanings for the language.
- 123alpha: identifier names cannot begin with numbers.
How to check the validity of Identifier names?
Python has a function which developers can use to check if an identifier name will be declared valid or not. It is the function identifier().
However, the limitation of this function is that it does not consider reserved keywords for identification.
To overcome this limitation, Python provides another function known as keyword identifier(). This function checks the validity of an identifier name while keeping the keywords in mind.
For example;
print(“xyz”.isidentifier())
print(“88x”.isidentifier())
print(“_”.isidentifier())
print(“while”.isidentifier())
Output:
True
False
True
True (incorrect output)
There is another function str.isidentifier(), that can determine whether an identifier name is valid or not.
What are the best practices for Naming Identifiers in Python?
Although following Python’s rules is enough for generating unique identifier names which will be declared valid, professionally, users are suggested to follow a certain naming practice. This reduces minute, unforeseen problems and errors while experimenting with different types of identifier names. Even though these errors may seem negligible and might not report syntax errors initially, they can lead to runtime, or logical errors can occur, consequently displaying unwanted results.
(For perspective, errors that occur in the code are known as syntax errors. When the syntax is correct, but the logic is wrong – ultimately leading the program towards a different path – the error is known as a runtime error.)
Here are the best naming practices for Identifiers in Python:
1. For Naming Constants:
- Use all uppercase or capital letters for names.
- Users can separate words by an underscore.
- Example: MAX_VALUE, SUMMATION_INDEX, etc.
2. For Package Names:
- Short names are preferred.
- Use of underscores is not advised.
- All characters should be in lowercase.
- Example: utilities, math, etc.
3. For Class Names
- It is advised to start class names with uppercase letters. For example, Matrix, Transpose, Shuffle, etc.
- For class names having multiple words, users can use capital letters for the starting alphabet of each word. For example, BubbleSort, ElectricBill, StandardData.
Apart from this Following are the Best Naming Practices for Identifiers in Python
- If the identifier consists of two underscores, one at the beginning and one at the end, the identifier name is a language-defined special. Users should avoid this technique of naming.
- Generally, names of functions that return Boolean values begin with ‘is’. For example, isstring, iskeyword, etc.
- Identifier names can be of any length. But one should keep it short and precise for efficient usage. Like, First_inputed_value is acceptable, but it is better to use InpValue_1
- Identifier names should be kept meaningful for a better understanding of the program. To provide examples, ‘HRAvalue: conveys the underlying message better than ‘Asdf0022’.
- Technically, one can use underscores as the first and last characters, but it is advised not to do so because that format is used for Python built-in types.
- If the names of variables models for functions contain more than one word, then it is better to separate them with an underscore. Example: is_true(), Input_array(), object_inputted, etc.
- Generally, module functions and variable names begin with lowercase alphabets. For example: dataentry(), pattern_1, etc.
upGrad’s Exclusive Data Science Webinar for you –
Transformation & Opportunities in Analytics & Insights
Also, Read Identity Operator in Python
Conclusion
Python is one of the most widely used programming languages of the current decade. The ease of use it facilitates while reducing complexities in coding has provided it with an edge over other contemporary programming languages.
Naming identifiers is one of the primary elements to understand when learning to code in Python. Identifiers, being user-defined names, are unique for every program. As long as the rules of naming are followed, the names are good to go. However, to increase efficiency within a given time frame, it is advised to follow certain naming practices which are universally accepted. We hope this article helped you learn about the basics of Python identifiers.
If you are interested in gaining more knowledge on Python’s building blocks, we recommend joining upGrad’s Data Science Program from IIIT Bangalore. The 18-month course comprises 500+ hours of content, 60+ case studies and projects, and global access to fantastic job opportunities. After completing this course, you can take on roles like Data Analyst, Data Scientist, Product Analyst, Machine Learning Engineer, Business Analyst.
Get in touch with us today to enrol in the program!
Explore our Popular Data Science Online courses
Top Data Science Skills to Learn to upskill
SL. No | Top Data Science Skills to Learn | |
1 |
Data Analysis Online Courses | Inferential Statistics Online Courses |
2 |
Hypothesis Testing Online Courses | Logistic Regression Online Courses |
3 |
Linear Regression Courses | Linear Algebra for Analysis Online Courses |
Read our popular Data Science Articles
Frequently Asked Questions (FAQs)
1. What are valid identifiers in Python?
Identifiers in Python can comprise both lowercase (a to z) and uppercase letters (A to Z). They can also include digits (0 to 9) and start with an underscore (_).
2. Give examples of valid identifiers in Python.
Here are a few examples of valid identifiers in Python:
1. FLAG
2. _789
3. userName
4. enter_user_details
3. Can keywords be used as identifiers?
No, identifiers can not have the same names as keywords. Note that there are 33 keywords in Python.