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How to Align Text in Two Columns with ljust in Python
Format pairs of strings into two aligned columns using ljust padding.
items = [
("apple", "red"),
("banana", "yellow"),
("cherry", "dark red"),
("date", "brown")
]
col1_width = max(len(name) for name, _ in items) + 2
for name, color in items:
print(name.ljust(col1_width) + color)How to Center Text in a Fixed-Width Banner in Python
Centers any text inside a fixed-width banner using fill characters and computed padding.
def center_text_banner(text, width=40, fill_char="="):
"""Center text within a fixed-width banner."""
if len(text) >= width:
return text
total_padding = width - len(text)
left_padding = total_padding // 2
right_padding = total_padding - left_padding
banner_line = fill_char * w…How to Convert snake_case to Title Case in Python
Convert snake_case strings to title case by splitting on underscores, capitalizing each word, and joining them with spaces.
def to_title_case(snake_str):
words = snake_str.split("_")
return " ".join(word.capitalize() for word in words)
if __name__ == "__main__":
examples = ["hello_world", "convert_snake_case", "already_title_case", "multiple__under_scores"]
for example in examples:
print(f"{example!r:35} -> {to_tit…How to Format Text in Python
A beginner-friendly helper that cleans and changes the case of a string, with options for title, upper, lower, and capitalize.
def format_text(text, case="title", strip_whitespace=True, remove_extra_spaces=True):
"""
Formats a string based on common beginner needs.
Args:
text: Input string to format
case: "title", "upper", "lower", or "capitalize"
strip_whitespace: Remove leading/trailing whitespace
…How to Format Text in Python (Beginner's Guide)
This beginner-friendly Python script demonstrates text formatting basics: stripping whitespace, converting to title case, replacing substrings, splitting into words, and generating a snippet.
text = " hello world, welcome to python skillset! "
cleaned = text.strip()
title_cased = cleaned.title()
replaced = title_cased.replace("Python", "PYTHON")
words = replaced.split()
word_count = len(words)
first_three = " ".join(words[:3])
snippet = first_three + "..."
print("Original:", repr(text))
print("Stripped:"…How to Format a Float as Currency in Python
This code defines a function that converts a float to a string formatted as US currency with two decimal places and comma separators.
def format_currency(amount):
return f"${amount:,.2f}"
if __name__ == "__main__":
test_amounts = [1234.5, 0, 9999999.999, -42.867]
for amount in test_amounts:
print(f"{amount} -> {format_currency(amount)}")How to Pad a String with Zeros in Python
Pad a string to a fixed width by left-filling it with zeros using the built-in str.zfill method.
def pad_zeros(s, width):
return s.zfill(width)
if __name__ == "__main__":
print(repr(pad_zeros("42", 6)))
print(repr(pad_zeros("-7", 5)))
print(repr(pad_zeros("hello", 10)))
print(repr(pad_zeros("123", 3)))How to Round Numbers with f-strings in Python
Round numbers directly inside f-string expressions using the built-in round() function for clean, readable output formatting.
def main():
# Values to format with expression-based rounding
price = 19.995
tax_rate = 0.0825
distance = 1234.56789
# Round inside the f-string expression using round()
print(f"Price rounded to cents: ${round(price, 2)}")
# Combine rounding with arithmetic inside the expression
total…How to wrap long text to a specified width in Python
Uses Python's textwrap.fill to wrap a long string to a specified width at word boundaries, preserving readability in console output or logs.
import textwrap
text = """This is a long piece of text that definitely exceeds the width limit
if we try to print it on a single line without any wrapping applied."""
wrapped = textwrap.fill(text, width=40)
print(wrapped)Format Lists of Tuples into Numbered Lines in Python
This code loops through a list of (name, grade) tuples and formats each into a numbered line using enumerate and f-strings.
def format_students(students):
formatted = []
for i, student in enumerate(students, start=1):
name, grade = student
formatted.append(f"{i}. {name}: {grade}")
return "\n".join(formatted)
if __name__ == "__main__":
students = [
("Alice", 92),
("Bob", 85),
("Charl…Format CLI help text in Python
Build a readable usage string for a command-line tool, aligning flags and wrapping descriptions with the textwrap module.
import textwrap
def format_help(command_name: str, description: str, options: list[tuple[str, str]]) -> str:
"""Format CLI help text into a readable usage string."""
header = f"Usage: {command_name} [OPTIONS]"
lines = [header, "", description, "", "Options:"]
for flag, help_text in options:
…How to Print Colored Text in Python with ANSI Codes
Define a small Colors class and a colored() helper to print styled terminal text using ANSI escape codes.
class Colors:
RESET = "\033[0m"
RED = "\033[31m"
GREEN = "\033[32m"
YELLOW = "\033[33m"
BLUE = "\033[34m"
MAGENTA = "\033[35m"
CYAN = "\033[36m"
WHITE = "\033[37m"
BOLD = "\033[1m"
UNDERLINE = "\033[4m"
def colored(text, color):
return f"{color}{text}{Colors.RESET}"
if _…How to Load and Save JSON Files in Python
Load and save JSON files with pretty formatting using Python's standard library json module and pathlib.
import json
from pathlib import Path
def load_json(filepath: str) -> dict:
"""Load JSON data from a file."""
path = Path(filepath)
with path.open("r", encoding="utf-8") as f:
return json.load(f)
def save_json(filepath: str, data: dict) -> None:
"""Save data to a JSON file with pretty format…How to Create a Data Formatter Class in Python
A beginner-friendly helper class to format lists, dictionaries, and stored records into readable strings.
class DataFormatter:
"""Helper class for beginners to format common data types."""
def __init__(self, name="data"):
self.name = name
self.records = []
def add_record(self, key, value):
"""Add a key-value record to the formatter."""
self.records.append({"key": key, …How to Use List Comprehensions and Generators to Format Data in Python
A beginner-friendly helper that formats dictionaries into strings using a list comprehension and generates squared numbers lazily with a generator.
def format_data(items):
"""Format a list of dictionaries into readable strings."""
formatted = [
f"{item.get('name', 'Unknown')}: {item.get('value', 0)} units"
for item in items
if item.get('value', 0) > 0
]
return formatted if formatted else ["No positive values found"]
def g…How to Append Few-Shot Examples to a Prompt in Python
This code builds a complete LLM prompt by appending few-shot examples in alternating user/assistant format using a simple loop.
def append_few_shot_examples(prompt: str, examples: list[tuple[str, str]], separator: str = "\n\n") -> str:
"""Append few-shot examples to a prompt in alternating user/assistant format."""
full_prompt = prompt
for user_input, assistant_output in examples:
full_prompt = f"{full_prompt}{separator}Use…Fill PDF Form Fields from a Mock Template in Python
Fills a PDF-style form template dictionary with user data, preserving template fields and formatting output as JSON.
import json
template = {
"first_name": "",
"last_name": "",
"email": "",
"phone": "",
"date_of_birth": "",
"address": "",
"city": "",
"state": "",
"zip_code": "",
"agree_to_terms": False
}
def fill_pdf_form(template: dict, data: dict) -> dict:
for key, value in data.items…Format Data with Type Hints in Python
Build a validated person dict with modern type hints and optional list handling.
from typing import Any, Dict, List, Optional, Union
JsonValue = Union[str, int, float, bool, None, List["JsonValue"], Dict[str, "JsonValue"]]
def format_person(name: str, age: int, hobbies: Optional[List[str]] = None) -> Dict[str, Any]:
"""Build a person dict with validated typing."""
if not name or age < 0:…How to Verify Formatted Output with an Approval Test in Python
Write a small Python approval test that verifies a function's exact formatted output using unittest.
import sys
from io import StringIO
import unittest
def generate_output(name, score):
return f"Player: {name} | Score: {score:03d}"
class TestFormattedOutput(unittest.TestCase):
def test_output_format(self):
expected = "Player: Alice | Score: 042"
result = generate_output("Alice", 42)
…Format data in Python using dataclasses like gRPC messages
Convert Python dataclasses to and from dicts and format them gRPC-style for clean data handling.
from dataclasses import dataclass
from typing import Any, Dict, List, Optional
@dataclass
class ProductInfo:
"""Data class representing a gRPC-style product message."""
name: str
price: float
tags: List[str]
description: Optional[str] = None
def to_dict(self) -> Dict[str, Any]:
"""C…Generate Prometheus Text Exposition Format in Python
Mock a Prometheus metrics endpoint by formatting metrics into the text exposition format with HELP, TYPE, and sample lines.
import time
from random import randint
# Mock a Prometheus metrics endpoint output
metrics = {
"http_requests_total": {
"help": "Total number of HTTP requests",
"type": "counter",
"samples": [
{"labels": {"method": "get", "code": "200"}, "value": randint(1000, 9999)},
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Guide: free Python code samples library
Copy-ready Python snippets for learners and developers
PythonSkillset code samples are short, focused examples organised by topic and difficulty. Every snippet is server-rendered HTML — readable by search engines and easy to copy. Open any sample, read the notes, copy the code, then press Try in editor to run it in the browser with Pyodide.
How to use this library
- Pick a topic section — strings, lists, files, functions, and more
- Open a sample, read How it works, and copy the code block
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Samples vs tutorials and challenges
Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.