- 01Environment Setup (what you'll need)
- 02Variables and print()
- 03Conditionals (if statements)
- 04Loops (for statements)
- 05Writing Your First Function
- 06Working with Lists
- 07Working with Dictionaries (dict)
- 08Loops (while statements)
- 09Working with Strings
- 10Introducing Classes (Object-Oriented Programming)
- 11Error Handling (try...except)
- 12List Comprehensions
- 13Generators and yield
- 14File Handling Basics
- 15The match Statement (Python's switch)
- 16The Conditional (Ternary) Expression
- 17Inheritance (Extending a Class)
- 18Writing Comments
- 19Logical Operators (and, or, not)
- 20Constants (values you agree not to change)
- 21Splitting and Joining Strings (split, join)
- 22Writing None-Safe Code
- 23Searching a List (in and finding the next match)
- 24Transforming a List with map()
- 25Two-Dimensional Lists (grid-shaped data)
- 26Writing a Custom Exception Class
- 27Default Arguments (initial parameter values)
- 28Working with Sets
- 29Checking Correctness with assert (your first step into testing)
- 30Higher-Order Functions (passing a function as an argument)
- 31Stacks and Queues (basic data structures)
- 32Type Conversion (casting) Basics
- 33Intro to Regular Expressions (pattern matching)
- 34The Binary Search Algorithm
- 35Building a Caesar Cipher (a character-shifting cipher)
- 36Understanding How Bubble Sort Works
- 37Building and Displaying Dates (basic year/month/day operations)
- 38Writing Multiple Test Cases Together
- 39Speeding Up Calculations with Memoization (caching)
- 40Normalizing Strings (strip, unifying case)
- 41Shallow Copy vs. Deep Copy
- 42Enum (Enumerated Types) Basics
- 43Flattening a List
- 44Reversing a String and Checking for Palindromes
- 45Pairing Up Two Lists (the zip operation)
- 46Rounding Numbers (floor, ceil, round)
- 47Multi-Line Strings (triple quotes)
- 48Functions That Return Multiple Values (tuples)
- 49Finding the GCD and LCM (the Euclidean algorithm)
- 50Formatting Numbers (padding digits, decimal places)
- 51Cleanup Logic with try/except/finally
- 52Writing Type-Agnostic Functions
- 53The with Statement (Context Managers) Basics
- 54Generating Random Numbers
- 55Bitwise Operators (AND, OR, XOR, shifts)
- 56Class Variables and @staticmethod Basics
- 57Waiting for a Fixed Amount of Time (time.sleep)
- 58Watch Out for Floating-Point Rounding Errors
- 59Type Hints Basics
- 60FizzBuzz (the classic practice problem)
- 61Checking Whether a Number Is Prime
- 62Set Operations (union, intersection, difference)
- 63Converting Number Bases (binary, hex)
- 64Checking Balanced Parentheses (an application of stacks)
- 65Checking Whether Two Words Are Anagrams
- 66Checking Whether a Year Is a Leap Year
- 67Converting Temperature (Celsius to Fahrenheit)
- 68Prime Factorization
- 69[Applied] Build a Household Budget Tool
Constants (values you agree not to change)
This lesson covers the conventional way of writing constants in Python, so you can clearly express a variable that isn't meant to be changed. It's written for anyone searching "Python constants tutorial".
Python has no dedicated syntax for constants like some other languages do, but the convention is to write the variable name in all capital letters to signal "this value isn't meant to change." It isn't enforced by the language itself, but it's a widely followed unwritten rule on real teams.
The sample code uses an all-caps variable name, MAX_SCORE, and displays its value in an f-string. Technically this variable can still be reassigned, but just by seeing the name, other developers understand the intent that it shouldn't be.
A common beginner mistake is not realizing Python has no language-level enforcement for constants. Even in all caps, the value can technically still be changed — following the "don't change this" convention is entirely up to the programmer's own discipline. Don't expect the same enforcement you'd get from const in other languages.
Because the intent is immediately clear to any reader, this convention is widely used for things like configuration values in large projects or managing API keys — often gathered together as all-caps variables in a dedicated settings file, a common real-world pattern.
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