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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

25 matches
Strings & text easy

Find Data From a String in Python: Stats, Clean, Keywords

Three helper functions for beginners: compute character/word/sentence stats, normalize whitespace and case, and extract unique sorted keywords from a string.

strings text-processing keywords
Python
def get_text_stats(text):
    """Return basic statistics about a string."""
    words = text.split()
    sentences = text.replace('!', '.').replace('?', '.').split('.')
    sentences = [s for s in sentences if s.strip()]
    return {
        'characters': len(text),
        'words': len(words),
        'sentences': le…
14 0 Open
Strings & text easy

How to Convert Data to Strings in Python

Convert common data types like bytes, numbers, containers, and None to readable strings with a safe helper function.

strings conversion type-conversion
Python
def to_str(value):
    """Convert common types to a readable string, safe for beginners."""
    if isinstance(value, bytes):
        return value.decode("utf-8")
    if isinstance(value, (dict, list, tuple, set)):
        return str(value)
    if value is None:
        return ""
    return str(value)


if __name__ == …
11 0 Open
Strings & text easy

How to Filter a List of Strings by Keyword in Python

A helper function filters a list of strings by a keyword search with optional case sensitivity.

string filter list
Python
def filter_strings(items, keyword, case_sensitive=False):
    """
    Filter a list of strings by a keyword.
    
    Args:
        items: list of strings to filter
        keyword: substring to search for
        case_sensitive: if True, match case exactly
    
    Returns:
        list of strings containing the keyw…
12 0 Open
Strings & text easy

How to Generate Text Helper Functions in Python

Three simple Python functions that repeat, join, and count characters in strings for beginners.

strings text-processing functions
Python
def repeat_text(text, times):
    """Repeat a string a given number of times."""
    return text * times


def join_words(words, separator=" "):
    """Join a list of words into a single string."""
    return separator.join(words)


def count_characters(text):
    """Count character occurrences in a string."""
    ret…
14 0 Open
Strings & text easy

How to Parse and Clean Text in Python

This code defines three helper functions to parse text into lowercase words, count unique word frequencies, and clean text by removing punctuation and extra whitespace.

text parsing string cleaning word frequency
Python
def extract_words(text: str) -> list[str]:
    """Return a list of lowercase words from the given text."""
    return [word.lower() for word in text.split() if word.isalpha()]


def count_unique_words(text: str) -> dict[str, int]:
    """Return a dictionary with unique words and their frequencies."""
    words = extra…
11 0 Open
Strings & text easy

How to Sort Text in Python with a Simple Helper Function

A compact helper function that sorts a list of strings or splits a string into words and sorts them alphabetically, with optional reverse ordering.

sorting strings text-processing
Python
def sort_text(data, reverse=False):
    """
    Sort a list of strings (or a single string split into words) alphabetically.
    """
    if isinstance(data, str):
        words = data.split()
    else:
        words = [str(item) for item in data]
    return sorted(words, reverse=reverse)


if __name__ == "__main__":
 …
11 0 Open
Strings & text easy

How to Transform Text in Python with a Helper Function

Build a simple Python helper to strip extra whitespace and convert text to upper, lower, or title case.

strings text helper
Python
def transform_text(text, upper=False, lower=False, strip_whitespace=False, title_case=False):
    """Apply common string transformations for beginners."""
    result = text

    if strip_whitespace:
        result = " ".join(result.split())

    if upper and lower:
        raise ValueError("Cannot apply both upper and…
12 0 Open
Strings & text easy

Python String Helper Functions for Beginners

A set of beginner-friendly Python functions that count words, reverse text, convert to title case, strip punctuation, and compute character frequency from a string.

strings text-processing word-count
Python
def count_words(text):
    """Count the number of words in a string."""
    return len(text.split())


def reverse_text(text):
    """Reverse the entire string."""
    return text[::-1]


def title_case(text):
    """Capitalize the first letter of each word."""
    return text.title()


def remove_punctuation(text):
 …
14 0 Open
Lists & loops easy

How to Filter Even Numbers and Square Them in Python

Create two beginner-friendly helper functions that filter even numbers and compute squares of a number list using loops, then print the results along with the sum and average.

loops filtering math
Python
def get_even_numbers(numbers):
    evens = []
    for num in numbers:
        if num % 2 == 0:
            evens.append(num)
    return evens

def get_squares(numbers):
    squares = []
    for num in numbers:
        squares.append(num ** 2)
    return squares

numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

even_numbers …
15 0 Open
Files & data easy

File Data Helper Functions in Python

Read and write text and JSON files, and list files in a directory, using pathlib-based helper functions.

file-io pathlib json
Python
from pathlib import Path

def load_text_file(filepath):
    """Read a text file and return its contents as a string."""
    path = Path(filepath)
    if not path.exists():
        raise FileNotFoundError(f"File not found: {filepath}")
    return path.read_text(encoding="utf-8")

def save_text_file(filepath, content):
…
14 0 Open
Files & data easy

How to Read and Write Text Files in Python

This code provides simple helper functions to save and load text files using Python's standard pathlib library.

file-io pathlib text-files
Python
from pathlib import Path


def save_text_data(filename: str, content: str) -> None:
    file_path = Path(filename)
    file_path.write_text(content, encoding="utf-8")


def load_text_data(filename: str) -> str:
    file_path = Path(filename)
    return file_path.read_text(encoding="utf-8")


if __name__ == "__main__":…
13 0 Open
Dictionaries & sets easy

Convert Lists and Dictionaries to Sets in Python

Convert lists of pairs into dictionaries and lists or dictionaries into sets using simple helper functions.

dict set conversion
Python
def convert_to_dict(data):
    """Convert list of tuples or lists into a dictionary."""
    return dict(data)


def convert_to_set(data):
    """Convert list or dictionary into a set of its keys/values."""
    if isinstance(data, dict):
        return set(data.keys())
    return set(data)


def convert_collection(data…
14 0 Open
Dictionaries & sets easy

Group Data by Key in Python with Dictionaries and Sets

Group items into a dictionary of sets using a key function, a beginner-friendly pattern for organizing data by categories.

grouping dictionaries sets
Python
def group_data(items, key_func):
    """Group items into a dictionary of sets based on a key function."""
    grouped = {}
    for item in items:
        key = key_func(item)
        if key not in grouped:
            grouped[key] = set()
        grouped[key].add(item)
    return grouped


if __name__ == "__main__":
 …
15 0 Open
Dictionaries & sets easy

How to Check Data Type and Inspect Dictionaries and Sets in Python

Inspect dictionaries and sets by printing their contents, types, and sizes using a small helper function.

dictionaries sets isinstance
Python
def check_data(data):
    """Helper to inspect dictionaries and sets."""
    if isinstance(data, dict):
        print(f"Dictionary with {len(data)} keys")
        for key, value in data.items():
            print(f"  {key}: {value} ({type(value).__name__})")
    elif isinstance(data, set):
        print(f"Set with {le…
13 0 Open
AI & LLM integration patterns easy

How to build a function calling schema dict in Python

Build an OpenAI-compatible function calling schema dictionary with a helper function that takes name, description, parameters, and required fields.

llm-api function-calling schema
Python
import json
from typing import Dict, Any, List, Optional


def build_function_schema(
    name: str,
    description: str,
    parameters: Optional[Dict[str, Any]] = None,
    required: Optional[List[str]] = None
) -> Dict[str, Any]:
    """Build an OpenAI-compatible function calling schema dictionary."""
    schema: …
14 0 Open
Data pipelines & processing easy

Create Data Helper Functions in Python for Beginners

Build reusable Python helper functions to load, filter, sort, summarize, and save JSON data — a beginner-friendly starting point for small data pipelines.

json pipeline helpers
Python
import json
from pathlib import Path
from typing import Any, Dict, List


def load_json_file(filepath: str) -> Dict[str, Any]:
    """Load JSON data from a file."""
    with Path(filepath).open("r", encoding="utf-8") as file:
        return json.load(file)


def filter_by_key(
    data: List[Dict[str, Any]], key: str,…
14 0 Open
Data pipelines & processing easy

How to Build Data Processing Functions in Python

Create reusable helper functions to load, filter, transform, and aggregate CSV data in Python.

csv pipeline etl
Python
import csv
from pathlib import Path


def load_data(filepath):
    """Load CSV data into a list of dicts."""
    with open(filepath, "r", newline="", encoding="utf-8") as f:
        return list(csv.DictReader(f))


def filter_rows(rows, column, value):
    """Keep rows where column equals value."""
    return [row for…
11 0 Open
Data pipelines & processing easy

How to Sort a List of Dictionaries by Key in Python

A reusable helper function that sorts a list of dictionaries by a specified key, with optional descending order support.

sorting dictionaries data-pipelines
Python
from typing import List

def sort_records(records: List[dict], key: str, descending: bool = False) -> List[dict]:
    """Sort a list of dictionaries by a specified key."""
    return sorted(records, key=lambda record: record[key], reverse=descending)


def demonstrate_sorting() -> None:
    users = [
        {"name": …
12 0 Open
Cloud + Python easy

How to Parse Cloud JSON Data in Python

A helper function that safely parses JSON payloads from cloud services into a clean dict with defaults and error handling.

json cloud parsing
Python
import json
from typing import Dict, Any

def parse_cloud_data(payload: str) -> Dict[str, Any]:
    """Parse a JSON payload from a cloud service into a clean dict."""
    try:
        data = json.loads(payload)
        return {
            "status": data.get("status", "unknown"),
            "region": data.get("region…
15 0 Open
Cloud + Python easy

How to Validate Data Fields and Types in Python

Validate required fields and type correctness in a Python dictionary with small helper functions, returning a list of clear error messages.

validation data dict
Python
import json
from typing import Any, Dict, List


def validate_data(data: Dict[str, Any], required_fields: List[str]) -> List[str]:
    """Check required fields exist and are non-empty. Return list of errors."""
    errors = []
    for field in required_fields:
        value = data.get(field)
        if value is None o…
13 0 Open
Modern tooling easy

Data Conversion Helper Functions in Python

A set of beginner-friendly helper functions to convert between JSON strings and Python data, parse dates, and read/write files using pathlib.

json datetime pathlib
Python
from datetime import datetime
from pathlib import Path
import json

def to_json(data, indent=2):
    """Convert Python data to pretty-printed JSON string."""
    return json.dumps(data, indent=indent, default=str)

def from_json(json_string):
    """Parse JSON string back into Python data."""
    return json.loads(jso…
12 0 Open
Modern tooling easy

How to Format Data with Python's datetime and JSON Helpers

A beginner-friendly set of helper functions to format dates and safely read/write JSON files in Python.

datetime json files
Python
from datetime import datetime
from pathlib import Path
import json


def format_today(pattern: str = "%Y-%m-%d") -> str:
    """Return today's date formatted with the given pattern."""
    return datetime.now().strftime(pattern)


def load_json(file_path: str) -> dict:
    """Read and parse a JSON file safely."""
    …
12 0 Open
Testing & modern typing easy

How to Group Data by Key in Python with Type Hints

Group a list of dictionaries by a specified key using a typed helper function and print a summary of each group.

grouping type-hints dictionaries
Python
from typing import Any, Dict, List, TypeVar, Union

T = TypeVar("T")

def group_by(data: List[Dict[str, Any]], key: str) -> Dict[Any, List[Dict[str, Any]]]:
    """Group a list of dictionaries by a given key."""
    grouped: Dict[Any, List[Dict[str, Any]]] = {}
    for item in data:
        value = item.get(key)
     …
12 0 Open
Testing & modern typing easy

How to Use TypedDict and Dataclasses in Python

Create typed data structures with TypedDict and dataclasses, then use them as helper functions for describing objects in a type-safe way.

typing typdict dataclass
Python
from typing import TypedDict, NotRequired, Optional
from dataclasses import dataclass


class User(TypedDict):
    name: str
    age: NotRequired[int]
    email: Optional[str]


@dataclass
class Product:
    id: int
    title: str
    price: float = 0.0


def describe_user(user: User) -> str:
    age = user.get("age",…
12 0 Open

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Each section groups closely related Python snippets.

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

  1. Pick a topic section — strings, lists, files, functions, and more
  2. Open a sample, read How it works, and copy the code block
  3. Run it in the IDE, tweak values, then take a related quiz or tutorial lesson

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.