Reference library

Python Code Samples

Easy snippets you can copy, study, and run in the browser editor.

207 matches
AI & LLM integration patterns easy

How to Validate LLM Output in Python

A beginner-friendly DataValidator class that checks required fields and type constraints on LLM-generated or user JSON data.

validation llm json
Python
import json
from typing import Any, Dict, List, Optional


class DataValidator:
    """Simple helper for validating LLM-generated or user data."""

    def __init__(self, required_fields: List[str], schema: Optional[Dict[str, str]] = None):
        self.required_fields = required_fields
        self.schema = schema or…
14 0 Open
AI & LLM integration patterns easy

Prepare LLM prompt data with a Python helper class

A beginner-friendly Python class that collects records, converts them to JSON, and produces a quick summary for building LLM prompt context.

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

class DataHelper:
    """Simple helper to prepare data for LLM prompts."""
    
    def __init__(self):
        self.data = []
    
    def add(self, item: Dict[str, Any]) -> "DataHelper":
        self.data.append(item)
        return self
    
    def to_json(self) -> s…
16 0 Open
AI & LLM integration patterns easy

Serialize and Format Data for LLM Prompts in Python

Use dataclasses and the json module to convert Python objects to JSON strings, parse them back, and format structured data into prompt-friendly text for LLM calls.

dataclasses json llm
Python
import json
from dataclasses import dataclass, asdict


@dataclass
class Recipe:
    """Simple data model to represent a recipe."""
    name: str
    cuisine: str
    prep_minutes: int


def to_json(recipe: Recipe) -> str:
    """Serialize a Recipe to a JSON string."""
    return json.dumps(asdict(recipe), indent=2)

…
14 0 Open
Automation & scripting easy

How to Generate a cloud-init User Data Mock in Python

Generate a cloud-init user data mock for a VM using a dataclass and JSON in Python.

cloud-init automation dataclasses
Python
import json
from dataclasses import dataclass, asdict

@dataclass
class VMConfig:
    hostname: str
    cpus: int
    memory_mb: int
    ssh_key: str

def generate_cloud_init_mock(config: VMConfig) -> str:
    """Build a cloud-init user-data mock for a VM."""
    user_data = {
        "hostname": config.hostname,
    …
14 0 Open
Automation & scripting easy

How to Merge PDFs in Python (Mock pypdf Stub)

Merge PDF files by concatenating their raw byte content using a simple stubbed class that mimics the pypdf interface.

pdf merge mock
Python
import io
from hashlib import sha256


class PdfStub:
    def __init__(self, data: bytes, name: str):
        self.data = data
        self.name = name

    def get_content_bytes(self) -> bytes:
        return self.data


def merge_pdfs_mock(pdf_stubs) -> bytes:
    merged = io.BytesIO()
    for stub in pdf_stubs:
   …
14 0 Open
Automation & scripting easy

How to Mock a Whisper API Transcription Stub in Python

Simulate an OpenAI Whisper-style transcription response with a dataclass request model and a mock function that returns structured audio transcription output.

mock whisper api-stub
Python
import json
from dataclasses import dataclass
from typing import Optional

@dataclass
class AudioRequest:
    file_path: str
    language: Optional[str] = None

    def to_api_payload(self) -> dict:
        return {"file": self.file_path, "language": self.language}

def mock_whisper_transcribe(payload: dict) -> dict:
…
15 0 Open
Automation & scripting easy

How to Save a VM Snapshot State to a JSON File in Python

Define a dataclass for a VM snapshot and serialize it to a JSON file, then reload it to verify the state.

json dataclass files
Python
import json
from dataclasses import dataclass, asdict
from pathlib import Path


@dataclass
class VMSnapshot:
    name: str
    memory_mb: int
    disk_gb: int
    state: str = "saved"

    def snapshot_to_file(self, path: Path) -> str:
        """Write snapshot state to a JSON file and return the filename."""
       …
13 0 Open
Automation & scripting easy

Mock systemctl Wrapper in Python for Service Testing

A Python class-based mock of systemctl that simulates start, stop, restart, and status operations for a service, useful for testing automation scripts.

systemctl mock automation
Python
import subprocess
import sys

class ServiceManager:
    def __init__(self, service_name):
        self.service_name = service_name
        self.status = "inactive"
    
    def start(self):
        self.status = "active"
        print(f"Starting {self.service_name}... OK")
    
    def stop(self):
        self.status …
14 0 Open
Automation & scripting easy

Resize Disk Partitions in Python (Mock Script)

A mock disk partition resize script that uses dataclasses to model partitions, validate new sizes, and output the updated layout as JSON.

disk partition dataclass
Python
#!/usr/bin/env python3
"""Mock script to demonstrate disk partition resize logic."""
import json
from dataclasses import dataclass
from typing import Dict


@dataclass
class Partition:
    name: str
    size_gb: int
    mount_point: str

    def to_dict(self) -> Dict[str, object]:
        return {
            "name": …
16 0 Open
Data pipelines & processing easy

Implement Exactly-Once Transaction Log in Python

A mock transaction log that deduplicates transaction IDs so each is recorded only once, with a dataclass for records and simple in-memory storage.

transactions deduplication dataclass
Python
from dataclasses import dataclass
from typing import Dict, Optional


@dataclass
class TxnRecord:
    txn_id: str
    status: str


class ExactlyOnceTxnLog:
    def __init__(self) -> None:
        self._log: Dict[str, TxnRecord] = {}
        self._processed_ids: set = set()

    def record(self, txn_id: str, status: s…
14 0 Open
Data pipelines & processing easy

Rollback dataset to previous snapshot pointer in Python

A SnapshotManager class stores timestamped data snapshots and rolls back to the most recent snapshot at or before a target time.

snapshots rollback datetime
Python
from datetime import datetime, timedelta


class SnapshotManager:
    def __init__(self):
        self.snapshots = {}  # timestamp -> data
        self.current_pointer = None

    def create_snapshot(self, data):
        timestamp = datetime.now()
        self.snapshots[timestamp] = data
        self.current_pointer =…
13 0 Open
Git + Python easy

How to Build a Git Helper Class in Python

A beginner-friendly GitHelper class that wraps common git commands (status, log, branch) into reusable Python methods with structured output.

git subprocess automation
Python
import subprocess
import json
from pathlib import Path


class GitHelper:
    def __init__(self, repo_path="."):
        self.repo = Path(repo_path)

    def run(self, *args):
        result = subprocess.run(
            ["git", *args],
            cwd=self.repo,
            capture_output=True,
            text=True,…
13 0 Open
Cloud + Python easy

Create a Cloud Storage Helper Class in Python

Build a simple local file-based helper class that mimics cloud storage operations like save, load, and list JSON objects.

cloud-storage json file-io
Python
import datetime
import json
from pathlib import Path


class CloudDataHelper:
    """Simple helper for reading/writing JSON files in a cloud-style folder."""

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

    def save_json(se…
17 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 =…
15 0 Open
Cloud + Python easy

How to Build a Multi-Cloud Config Loader with Provider Switching in Python

Load cloud provider configurations (AWS, Azure, GCP) from JSON files using a provider dispatch pattern in Python.

cloud config json
Python
import json
from pathlib import Path
from dataclasses import dataclass
from typing import Dict, Any


@dataclass
class CloudConfig:
    provider: str
    region: str
    settings: Dict[str, Any]


class ConfigLoader:
    def __init__(self, config_dir: str = "configs"):
        self.config_dir = Path(config_dir)
      …
13 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):
        …
13 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…
12 0 Open
Cloud + Python easy

How to Enforce Tag Policies on AWS Resources in Python

Build a reusable Python class that checks AWS resources against a required-tag policy and reports compliance with missing tags.

aws tagging compliance
Python
import json
from dataclasses import dataclass, field
from typing import Dict, List


@dataclass
class Resource:
    arn: str
    tags: Dict[str, str] = field(default_factory=dict)


class TagPolicyEnforcer:
    def __init__(self, required_tags: List[str]):
        self.required_tags = set(required_tags)

    def enfor…
15 0 Open
Cloud + Python easy

How to Implement Region Failover Config in Python with Primary and Secondary Mock

This Python class simulates regional failover: it tracks active region, switches to secondary on primary failure, and allows manual recovery.

failover cloud region
Python
import time

class RegionFailoverConfig:
    def __init__(self, primary, secondary):
        self.primary = primary
        self.secondary = secondary
        self.active = primary
        self.failover_count = 0
        self.healthy = True

    def check_health(self):
        """Mock health check - returns True if ac…
15 0 Open
Cloud + Python easy

Mock AWS Spot Instance Interruption Handler in Python

A Python class that simulates AWS Spot instance interruption checks, handling the 10% chance of termination, logging state-saving, and storing notice details.

aws spot-instances simulation
Python
import time
import random

class SpotInstanceHandler:
    def __init__(self, instance_id):
        self.instance_id = instance_id
        self.interruption_notices = []

    def start(self):
        print(f"Spot instance {self.instance_id} started")

    def check_interruption(self):
        # Simulate random interrup…
13 0 Open
Cloud + Python easy

Mock Azure Blob Upload and Download in Python

Simulate Azure Blob Storage upload and download operations with a lightweight in-memory mock class for testing.

azure mock testing
Python
import io
import json
from datetime import datetime, timezone

class MockBlob:
    def __init__(self, name):
        self.name = name
        self.content = b""
        self.properties = {
            "last_modified": datetime.now(timezone.utc).isoformat(),
            "size": 0,
        }

    def upload(self, data, …
14 0 Open
Modern tooling easy

How to Build a Chainable Filter Helper in Python

A beginner-friendly dataclass helper that chains filters, uniqueness, and slicing on any sequence, returning a plain list at the end.

dataclass chaining filter
Python
from dataclasses import dataclass
from typing import Callable, Iterator, Sequence, TypeVar

T = TypeVar("T")


@dataclass
class FilterAssistant:
    """Beginner-friendly helper to filter any collection."""

    data: Sequence[T]

    def where(self, predicate: Callable[[T], bool]) -> "FilterAssistant":
        return …
15 0 Open
Modern tooling easy

How to Load and Inspect CSV Data with a Dataclass Helper in Python

This code defines a DataHelper dataclass that reads a CSV file into a list of dictionaries and prints basic dataset information.

csv dataclass pathlib
Python
from pathlib import Path
from dataclasses import dataclass
from typing import Any


@dataclass
class DataHelper:
    """Simple helper for loading and inspecting CSV data."""
    filepath: Path

    def load_csv(self, *, delimiter: str = ",") -> list[dict[str, Any]]:
        """Read CSV into a list of dictionaries."""
…
16 0 Open
Modern tooling easy

How to Load and Inspect Data Files in Python

A beginner-friendly DataLoader dataclass that loads JSON or text files and provides methods to preview and inspect the data.

dataclasses file-io json
Python
from dataclasses import dataclass, field
from pathlib import Path
import json
from typing import Any, Dict, List


@dataclass
class DataLoader:
    """Simple helper to load and inspect data files for beginners."""
    path: Path
    data: Any = field(init=False, default=None)

    def __post_init__(self) -> None:
    …
16 0 Open

Browse by section

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.