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SkillSnap Official GuideUpdated 7/24/2026
Python
The language of simplicity and power. Master list comprehensions, decorators, and the standard library to write truly 'Pythonic' code.
Pythonic Syntax & Sugar
List Comprehension (Faster than loops)[x**2 for x in range(10)]
F-Strings (Fastest string interpolation)f"Hello {name}"
Swap variables (No temp var)a, b = b, a
Walrus Operator (Assign inside expression)if (n := len(data)) > 10
Get index and value in loopenumerate(list)
Iterate two lists in parallelzip(a, b)
Placeholder for ignored variables_ (Underscore)
Data Structures (Std Lib)
Safe lookup (No KeyError)dict.get(key, default)
Auto-create missing keyscollections.defaultdict
Count item occurrences instantlycollections.Counter
Fast O(1) appends/pops from both endscollections.deque
O(1) membership testing / Remove duplicatesset(list)
Functions & Flow
Anonymous one-line functionlambda x: x + 1
Wrap/Modify function behavior@decorator
Capture variable arguments*args / **kwargs
Auto-cache function resultsfunctools.lru_cache
Run if loop didn't breakfor ... else
Object-Oriented (OOP)
Auto-gen __init__, __repr__, __eq__@dataclass
Reduce memory usage (No __dict__)__slots__
Getter/Setter syntax@property
Developer-friendly string representation__repr__
System & Performance
Context Manager (Auto-close file)with open(...) as f
Object-oriented file pathspathlib.Path
Generator (Lazy memory usage)yield
Async/Await for I/O bound tasksasyncio
Bypass GIL for CPU bound tasksmultiprocessing
Quality & Environment
Create Virtual Environmentpython -m venv .venv
Export dependenciespip freeze > req.txt
Run only if executed directlyif __name__ == "__main__":
Trigger Debugger (PDB)breakpoint()
Type Hint (Union[int, None])Optional[int]