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Functions & basics

Reusable building blocks — parameters, returns, scope, and clear function design.

5 matches

Build a Progress Callback Function for Loops in Python

Create a reusable progress callback that receives per-step data and lets callers log or update a UI as a loop runs.

def run_with_progress(items, desc="Processing", step_callback=None):
    """Run a loop with progress updates via callback."""
    total = len(items)
    for idx, item in enumerate(items):
        # Process the item (simulated work here)
        result = item * 2

        # Build progress data dictionary
        if ste…

16 0 Open

Functions & basics easy

Calculate Time Difference Across Time Zones in Python

Compute the current time difference in hours between two time zones given their UTC offsets using Python's datetime and timezone modules.

datetime timezone timedelta

Python

from datetime import datetime, timezone, timedelta

def time_difference(from_tz_offset, to_tz_offset):
    """
    Calculate time difference in hours between two time zones given their offsets from UTC.
    Offsets are in hours (e.g., -5 for EST, +5.5 for IST).
    """
    tz1 = timezone(timedelta(hours=from_tz_offset…

48 0 Open

Functions & basics medium

How to Invalidate Cache When Arguments Change in Python

A memoization decorator that caches function results keyed by arguments, automatically invalidating when inputs change.

decorators caching memoization

Python

from functools import wraps

def memoize(func):
    cache = {}
    
    @wraps(func)
    def wrapper(*args, **kwargs):
        key = (args, tuple(sorted(kwargs.items())))
        if key not in cache:
            cache[key] = func(*args, **kwargs)
        return cache[key]
    
    return wrapper

@memoize
def expensiv…

16 0 Open

Functions & basics easy

How to Validate CLI Integer Option Within a Range in Python

Use argparse with integer type and bounds checking to validate a command-line option falls within a specified min-max range.

argparse cli validation

Python

import argparse

def main():
    parser = argparse.ArgumentParser(description="Validate an integer within a range.")
    parser.add_argument("--value", type=int, required=True, help="Integer to validate")
    parser.add_argument("--min", type=int, default=0, help="Minimum allowed value")
    parser.add_argument("--max…

14 0 Open

Functions & basics easy

How to Validate Function Arguments in Python

Shows how to manually check argument types and values in a Python function, raising clear TypeError and ValueError messages.

validation function arguments type hints

Python

def calculate_area(length: float, width: float) -> float:
    """Calculate the area of a rectangle with manual type validation."""
    if not isinstance(length, (int, float)) or isinstance(length, bool):
        raise TypeError(f"length must be a number, got {type(length).__name__}")
    if not isinstance(width, (int,…

13 0 Open

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