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Python Code Samples

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

5 matches
Errors & debugging easy

How to Validate Input and Raise TypeError in Python

Define a function that checks its argument type and raises a TypeError early with a clear message when given a non-number.

type checking validation typeerror
Python
def validate_number(value):
    if not isinstance(value, (int, float)):
        raise TypeError(f"Expected a number, got {type(value).__name__}")
    return value * 2

if __name__ == "__main__":
    try:
        print(validate_number(5))
        print(validate_number("hello"))
    except TypeError as e:
        print(…
13 0 Open
OOP & classes easy

How to Validate Data Types in Python with a Class

A beginner-friendly Python class that checks if a value is a string, integer, float, list, or empty, using simple methods and isinstance checks.

class validation type checking
Python
class DataValidator:
    """A simple data validation helper for beginners."""
    
    def __init__(self, data):
        self.data = data
    
    def is_string(self):
        return isinstance(self.data, str)
    
    def is_integer(self):
        return isinstance(self.data, int) and not isinstance(self.data, bool)
…
13 0 Open
AI & LLM integration patterns easy

How to Validate JSON Output Against a Dict Schema in Python

Validate JSON-like data against a simple dict schema with type checking and descriptive error messages using only the Python standard library.

json validation schema
Python
from typing import Dict, Any, List, Union

def validate_json(data: Any, schema: Dict[str, str]) -> List[str]:
    """
    Validate JSON-like data against a simple dict schema.
    Schema format: {field_name: expected_type} where type is one of:
    'str', 'int', 'float', 'bool', 'list', 'dict', 'any'
    Returns list …
13 0 Open
Testing & modern typing easy

How to Use Literal Type Hints in Python

Use typing.Literal to restrict a function parameter to specific allowed string values and get static type checking.

typing type-hints literal
Python
from typing import Literal

def get_status_message(status: Literal["active", "inactive", "pending"]) -> str:
    """Return a message based on the status value."""
    if status == "active":
        return "Account is active"
    elif status == "inactive":
        return "Account is inactive"
    else:
        return "…
15 0 Open
Testing & modern typing easy

How to Use TypedDict for Structured Dict Typing in Python

Define and use TypedDict to add type hints to dictionaries, improving code clarity and enabling static type checking in your Python projects.

typing typeddict type-hints
Python
from typing import TypedDict


class User(TypedDict):
    name: str
    age: int
    email: str


def greet(user: User) -> str:
    return f"Hello {user['name']}, age {user['age']}, contact {user['email']}"


if __name__ == "__main__":
    alice: User = {"name": "Alice", "age": 30, "email": "alice@example.com"}
    pr…
12 0 Open

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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.