Python

Practice typing real Python code. From variables and functions to classes, file I/O, and exception handling.

Variables & Data Types

Practice declaring variables with different Python data types.

Basic variable assignments with str, int, and bool
Type-annotated variable declarations
Arithmetic operations with variables
Tuple unpacking and variable swapping

Functions & Decorators

Type function definitions, lambda expressions, and decorators.

Function with type annotations and f-string
Function with default parameter returning a dict
Lambda expressions for simple operations
Decorator function with args and kwargs
Using a decorator with arguments

Strings & F-Strings

Practice string methods and f-string formatting expressions.

F-strings with embedded expressions
Common string methods
Splitting, joining, and membership testing
F-string format specifiers for numbers and alignment

Lists & List Comprehensions

Type list operations and comprehension expressions.

List creation with append and pop
List comprehensions with and without filtering
Nested list comprehension to flatten
Sorting with key function and reversing
Extended unpacking and slice notation

Dictionaries & Sets

Practice dictionary and set operations with comprehensions.

Dictionary literal with multiple key-value pairs
Dict methods: get with default, keys, and items
Dictionary unpacking and dict comprehension
Set creation and set operations

Conditionals & Pattern Matching

Type if/elif/else blocks and structural pattern matching.

Basic if/elif/else conditional block
Inline conditional (ternary) expressions
Structural pattern matching with match/case
Using all() and any() with generator expressions

Loops & Generators

Practice for loops, while loops, and generator functions.

Basic for loops with range and iterable
Enumerate and dict iteration with unpacking
While loop with break and else clause
Generator function with yield
Generator expression and zip

Classes & Inheritance

Type class definitions with dunder methods and inheritance.

Basic class with __init__ and method
Class inheritance with method override
Dataclass with type annotations and method
Singleton pattern using __new__

File I/O & Context Managers

Practice file operations and context manager patterns.

Reading a file with context manager
Writing CSV data with a context manager
Reading and writing JSON files
Path operations with pathlib

Exception Handling

Type try/except/finally blocks and custom exceptions.

Basic try/except for type conversion
Multiple except clauses with finally
Custom exception class with attributes
Raising an exception with a message
Logging and re-raising an exception

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