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Python Code Samples

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

35 matches
Lists & loops easy

Generate Data Helper for Beginners in Python

Define two functions that create a random list of integers and then compute basic summary statistics like count, total, average, maximum, and minimum using simple loops.

random loops lists
Python
from random import randint

def build_dataset(size: int, max_val: int) -> list[int]:
    data = []
    for _ in range(size):
        data.append(randint(1, max_val))
    return data

def summarize(data: list[int]) -> dict[str, float]:
    total = 0
    maximum = data[0]
    minimum = data[0]
    for value in data:
   …
12 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
Dictionaries & sets easy

Compare Two Dictionaries in Python

Compare two dictionaries by finding common keys, unique keys, and value differences using Python's set operations.

dictionary set operations comparison
Python
def compare_data(dict1, dict2):
    """Compare two dictionaries and summarize similarities/differences."""
    keys1 = set(dict1.keys())
    keys2 = set(dict2.keys())
    
    common_keys = keys1 & keys2
    only_in_first = keys1 - keys2
    only_in_second = keys2 - keys1
    
    print(f"Common keys ({len(common_keys…
18 0 Open
Dictionaries & sets easy

How to Group Data by Category in Python with a Split Data Helper

This code groups a list of (category, item) pairs into a dictionary where each key is a category and each value is a list of items belonging to that category.

dictionary grouping iterable
Python
def split_data(categories):
    """
    Group data items into buckets based on a key function.
    Returns a dict where keys are bucket names and values are lists of items.
    """
    buckets = {}
    for category, item in categories:
        if category not in buckets:
            buckets[category] = []
        buck…
14 0 Open
OOP & classes easy

Design a Data Helper Class in Python

Create a simple Object-Oriented data helper with DataPoint and Dataset classes that store, describe, and summarize coordinate points.

oop classes data-helper
Python
class DataPoint:
    def __init__(self, x, y):
        self.x = x
        self.y = y
        self.label = None

    def describe(self):
        """Return a human-readable description of the data point."""
        base = f"DataPoint(x={self.x}, y={self.y})"
        return f"{base}, label='{self.label}'" if self.label e…
15 0 Open
OOP & classes easy

Group Data Helper Class in Python

A simple Python class that stores items under named groups, retrieves groups, items, and counts, and formats them as a readable summary.

class grouping helper
Python
class GroupData:
    """A simple helper class to store and group data for beginners."""

    def __init__(self):
        self.items = []

    def add(self, item, group):
        """Add an item under a given group name."""
        self.items.append({"item": item, "group": group})

    def get_groups(self):
        """R…
14 0 Open
OOP & classes easy

How to Build a Data Helper Class in Python with OOP

Create a beginner-friendly Python class that loads CSV data, filters records by field, and counts entries using object-oriented programming.

oop csv data
Python
class DataHelper:
    """A beginner-friendly OOP helper for handling simple datasets."""
    
    def __init__(self, filename):
        self.filename = filename
        self.data = self._load_data()
    
    def _load_data(self):
        """Load data from a CSV file into a list of dictionaries."""
        import csv
 …
12 0 Open
OOP & classes easy

How to Create a Data Helper Class in Python with OOP

A complete OOP example with User, Post, and Blog classes that manage data relationships and provide clear helper methods.

oop classes data-modeling
Python
class User:
    def __init__(self, name, email):
        self.name = name
        self.email = email
        self.posts = []

    def create_post(self, title, content):
        post = Post(title, content, self)
        self.posts.append(post)
        return post

    def get_post_count(self):
        return len(self.p…
12 0 Open
Comprehensions & generators easy

Write Data Helpers with Comprehensions and Generators in Python

Demonstrates list, dict, and set comprehensions plus generator expressions and generator functions for building concise data helpers.

comprehensions generators data-helpers
Python
# Basic comprehensions and generators demo

# List comprehension: squares of evens
squares = [x * x for x in range(10) if x % 2 == 0]
print("List comp:", squares)

# Dictionary comprehension: char -> count
text = "hello"
char_counts = {c: text.count(c) for c in set(text)}
print("Dict comp:", char_counts)

# Set compre…
10 0 Open
AI & LLM integration patterns medium

How to Build a Data Helper for LLM Prompts in Python

A beginner-friendly helper class that flattens nested dictionaries, formats prompt templates, and safely parses JSON for AI/LLM pipelines.

llm prompt-engineering data-prep
Python
import json
from typing import Any, Dict, List, Optional


class DataHelper:
    """Simple helper class for working with data in AI/LLM pipelines."""
    
    def __init__(self, data: Optional[Dict[str, Any]] = None) -> None:
        self.data = data or {}
    
    def flatten(self, prefix: str = "") -> Dict[str, Any]…
17 0 Open
AI & LLM integration patterns easy

How to Create a Simple Data Helper in Python for LLM Projects

Create a beginner-friendly Python class that stores, filters, and serializes data records for AI/LLM workflows.

data-helper json llm
Python
import json
from typing import Any, Dict, List, Optional


class DataHelper:
    """Simple helper for beginners to manage data in AI/LLM projects."""

    def __init__(self, data: Optional[List[Dict[str, Any]]] = None) -> None:
        self.data: List[Dict[str, Any]] = data or []

    def add_item(self, item: Dict[str…
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 Process CSV Data in Python with a Data Helper

Build a beginner-friendly data helper in Python that loads a CSV file, filters rows by a condition, and summarizes numeric fields.

csv data-processing pathlib
Python
import csv
from pathlib import Path

DATA = [
    {"name": "Alice", "score": 88, "passed": True},
    {"name": "Bob", "score": 42, "passed": False},
    {"name": "Carol", "score": 95, "passed": True},
]


def load_csv(file_path: Path) -> list[dict]:
    with file_path.open(newline="", encoding="utf-8") as f:
        r…
13 0 Open
Cloud + Python easy

Create a Data Helper Class for Beginners in Python

A simple Python class to read and write JSON and CSV files from a local directory, ideal for automating data workflows in cloud environments.

json csv file-io
Python
import json
from pathlib import Path

class DataHelper:
    """Simple helper for reading and writing common data files."""
    
    def __init__(self, directory="data"):
        self.directory = Path(directory)
        self.directory.mkdir(exist_ok=True)
    
    def save_json(self, filename, data):
        filepath =…
14 0 Open
Cloud + Python easy

How to Create a JSON Data Helper in Python

A beginner-friendly DataHelper class that safely reads and writes JSON files with timestamps to a local data directory.

json files data-helper
Python
from datetime import datetime
from pathlib import Path
import json


class DataHelper:
    """Simple helper for reading/writing JSON files safely."""

    def __init__(self, base_dir="data"):
        self.base_dir = Path(base_dir)
        self.base_dir.mkdir(exist_ok=True)

    def save(self, filename, data):
        …
12 0 Open
Cloud + Python easy

How to Design a Cloud Data Helper Class in Python

A beginner-friendly Python helper class that saves, loads, and aggregates JSON records locally, simulating cloud-style data handling.

cloud json helper
Python
import json
from pathlib import Path
from datetime import datetime


class CloudDataHelper:
    """Beginner-friendly helper for working with cloud-based JSON data."""

    def __init__(self, base_dir="cloud_data"):
        self.base_dir = Path(base_dir)
        self.base_dir.mkdir(exist_ok=True)

    def save_record(s…
11 0 Open
Modern tooling easy

How to Load and Save CSV and JSON Files in Python

A beginner-friendly data helper that loads or saves CSV and JSON files using only the Python standard library, with automatic format detection from the file extension.

csv json file-io
Python
from pathlib import Path
import json
import csv


def load_data(file_path):
    """Load CSV or JSON data from disk based on file extension."""
    path = Path(file_path)
    if path.suffix == ".json":
        with path.open() as f:
            return json.load(f)
    elif path.suffix == ".csv":
        with path.open(…
13 0 Open
Modern tooling easy

How to Save and Load JSON Files in Python

Create a simple data helper to save Python dictionaries as pretty-printed JSON files and load them back reliably using pathlib and the stdlib json module.

json pathlib file-io
Python
import json
from pathlib import Path
from typing import Any


def save_json(data: Any, filename: str) -> None:
    """Save data as pretty-printed JSON to the current directory."""
    path = Path(filename)
    with path.open("w", encoding="utf-8") as f:
        json.dump(data, f, indent=2, ensure_ascii=False)


def lo…
11 0 Open
Testing & modern typing easy

Design Data Helpers with Python TypedDict and Literal

Use TypedDict, Literal, and Union to define typed data shapes and parse values in Python.

typeddict literal union
Python
from typing import TypedDict, Literal, Optional, Union, List

class User(TypedDict):
    name: str
    age: int
    role: Literal["admin", "user", "guest"]

def describeUser(data: User) -> str:
    return f"{data['name']} ({data['age']}) — {data['role']}"

def parse_value(item: Union[int, str, None]) -> str:
    if it…
12 0 Open
Testing & modern typing easy

How to Filter Data in Python with Type Hints

A reusable filter_data helper uses optional predicates and numeric bounds with modern Python type hints.

filtering type-hints generics
Python
from typing import Iterable, TypeVar, Callable, Any

T = TypeVar("T")

def filter_data(
    items: Iterable[T],
    predicate: Callable[[T], bool] | None = None,
    *,
    min_value: float | None = None,
    max_value: float | None = None,
) -> list[T]:
    """Filter items by predicate and/or numeric bounds."""
    r…
11 0 Open
Testing & modern typing easy

How to Use Python Type Hints for Beginners

Build a data helper module with basic type hints — Union, Optional, List, Dict, Any, and TypeVar — to make your code clearer and safer.

type-hints typing annotations
Python
from typing import Any, Union, Optional, List, Dict, Tuple, Callable, TypeVar

T = TypeVar("T")

def describe(value: Any) -> str:
    """Return a human-readable description of the value's type."""
    if isinstance(value, list):
        return f"list of {len(value)} items"
    elif isinstance(value, dict):
        ret…
13 0 Open
System design patterns easy

Create a Data Helper Class in Python

A reusable DataHelper class that saves and loads JSON and CSV files from a configurable base directory, with automatic header detection for CSV.

data-helper json csv
Python
import json
import csv
from pathlib import Path

class DataHelper:
    def __init__(self, base_path="."):
        self.base_path = Path(base_path)
        self.base_path.mkdir(exist_ok=True)

    def save_json(self, data, filename):
        path = self.base_path / filename
        with open(path, "w") as f:
          …
15 0 Open
System design patterns easy

How to Implement a Data Helper Class in Python

Build a beginner-friendly DataHelper class using dataclasses and key system design patterns like Command, Strategy, and Map.

dataclass data-helper design-patterns
Python
from __future__ import annotations
from dataclasses import dataclass, field
from typing import Any, Dict, List, Optional


@dataclass
class DataHelper:
    """A beginner-friendly data utility with common system design patterns."""
    data: List[Dict[str, Any]] = field(default_factory=list)

    def add_record(self, r…
13 0 Open
API design & gRPC easy

Create a Data Helper in Python for gRPC-style APIs

This code builds a simple DataHelper class that mimics gRPC request/response handling with in-memory storage, JSON serialization, and basic CRUD operations for beginners.

dataclasses grpc api-design
Python
import json
from dataclasses import dataclass, asdict
from typing import Dict, Any


@dataclass
class User:
    user_id: int
    name: str
    email: str


class DataHelper:
    """Simple helper to demonstrate gRPC-like data handling for beginners."""

    def __init__(self) -> None:
        self._users: Dict[int, Use…
15 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.