Reference library

Python Code Samples

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

1685 matches
Strings & text easy

How to Strip Whitespace in Python

This code demonstrates how to remove leading and trailing whitespace from a string using the built-in strip() method.

string whitespace text-cleaning
Python
def strip_whitespace(text: str) -> str:
    return text.strip()

if __name__ == "__main__":
    sample = "   Hello, world!   "
    result = strip_whitespace(sample)
    print(f"Original: '{sample}'")
    print(f"Stripped: '{result}'")
14 0 Open
Strings & text easy

How to Summarize Text Statistics in Python

This function returns basic statistics about a string, including character, word, and sentence counts, plus case and digit counts.

strings text-processing statistics
Python
def summarize_text(text):
    """Return basic statistics about a string."""
    words = text.split()
    return {
        "characters": len(text),
        "words": len(words),
        "sentences": text.count(".") + text.count("!") + text.count("?"),
        "uppercase": sum(c.isupper() for c in text),
        "lowerca…
13 0 Open
Strings & text easy

How to Translate Characters in a String with str.maketrans in Python

Build and apply character translation tables with str.maketrans and str.translate to replace, delete, or remap letters in a Python string.

string translation character-mapping
Python
def translate_demo():
    # Build a translation table: a→1, e→2, i→3, o→4, u→5
    table = str.maketrans("aeiou", "12345")
    
    text = "Hello, Python world! Keep coding, friend."
    translated = text.translate(table)
    
    print(f"Original: {text}")
    print(f"Translated: {translated}")
    
    # Example wit…
11 0 Open
Strings & text easy

How to Use Template Strings for Substitution in Python

This code shows how to use Python's Template class for safe string substitution, replacing placeholders like $name with actual values.

template string substitution
Python
from string import Template

def format_user_message(name, role, company):
    template = Template("Hello $name! We are glad to have you as our $role at $company.")
    return template.substitute(name=name, role=role, company=company)

if __name__ == "__main__":
    result = format_user_message("Alice", "Python Develo…
11 0 Open
Strings & text easy

How to Validate Text Input in Python: A Simple Text Processor

A Python function that validates a text string by trimming whitespace, then returns a dictionary with character, word, and sentence counts.

text-validation strings input-checking
Python
def validate_text(text: str) -> dict:
    """Analyze a text string and return basic validation statistics."""
    stripped = text.strip()
    if not stripped:
        return {
            "valid": False,
            "reason": "Text is empty or only whitespace",
            "characters": 0,
            "words": 0,
    …
11 0 Open
Strings & text easy

How to Validate Text Strings in Python

Validate strings with a reusable helper that checks type, length limits, and empty string handling.

validation strings helper-function
Python
def is_valid_text(value, min_length=1, max_length=None, allow_empty=False):
    """
    Validate if a value is a string and meets length requirements.
    
    Args:
        value: The value to validate
        min_length: Minimum allowed length (default 1)
        max_length: Maximum allowed length (None = no limit)
…
13 0 Open
Strings & text easy

How to build a text helper in Python for beginners

This code provides easy-to-use functions for cleaning text, removing punctuation, counting word frequencies, and summarizing strings — perfect for beginners.

string-manipulation text-processing word-count
Python
def clean_text(text: str) -> str:
    """Clean and normalize a text string."""
    text = text.strip()
    text = text.replace("  ", " ")
    text = text.capitalize()
    text = text.replace(".", ".")
    return text


def remove_punctuation(text: str) -> str:
    """Remove common punctuation marks from a string."""
 …
12 0 Open
Strings & text easy

How to remove punctuation from a string in Python

Remove all punctuation characters from a string using the str.translate method and string.punctuation from the standard library.

string punctuation translate
Python
import string

def remove_punctuation(text: str) -> str:
    return text.translate(str.maketrans("", "", string.punctuation))

if __name__ == "__main__":
    sample = "Hello, world! It's a test... (with punctuation) - done?"
    cleaned = remove_punctuation(sample)
    print(f"Original: {sample}")
    print(f"Cleaned:…
14 0 Open
Strings & text easy

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.

textwrap text wrapping formatting
Python
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)
11 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
Strings & text easy

Python: Replace Spaces with Hyphens for Slug

Transform a string by stripping surrounding whitespace and replacing each space with a hyphen to create a simple slug.

strings replace slug
Python
def slugify(text):
    return text.strip().replace(" ", "-")

if __name__ == "__main__":
    title = "Hello World Python Example"
    result = slugify(title)
    print(result)
12 0 Open
Strings & text easy

Remove Substring Occurrences Case-Insensitively in Python

This code removes every case-insensitive occurrence of a given substring from a text string using a simple looping approach.

strings case-insensitive substring
Python
def remove_occurrences_ci(text: str, substring: str) -> str:
    """Remove all case-insensitive occurrences of substring from text."""
    if not substring:
        return text
    
    result = []
    i = 0
    lower_text = text.lower()
    lower_sub = substring.lower()
    sub_len = len(substring)
    
    while i <…
12 0 Open
Strings & text easy

Repeat a string n times with a separator in Python

Repeats a string a given number of times, joining the repetitions with an optional separator, with a guard for non-positive counts.

strings repeat join
Python
def repeat_string_with_separator(s, n, sep=''):
    """
    Repeats a string n times, joining with a separator.
    
    Args:
        s (str): The string to repeat.
        n (int): Number of repetitions.
        sep (str): Separator between repetitions (default: '').
    
    Returns:
        str: The repeated strin…
11 0 Open
Strings & text easy

Reverse Words in a Sentence While Keeping Punctuation in Python

Reverses the order of words in a sentence while leaving punctuation and spaces in their original positions using Python's re module.

strings punctuation regex
Python
def reverse_words_preserving_punctuation(sentence: str) -> str:
    import re
    # Split into words and punctuation tokens
    tokens = re.findall(r'\w+|[^\w\s]|\s+', sentence)
    words = [t for t in tokens if re.fullmatch(r'\w+', t)]
    words.reverse()
    result_parts = []
    word_index = 0
    for token in toke…
13 0 Open
Strings & text easy

String helpers in Python: stats, reverse, and remove vowels

Three beginner-friendly Python functions compute text statistics, reverse word order, and strip vowels from a string.

string-manipulation text-stats vowel-removal
Python
def text_stats(text: str) -> dict:
    """Return basic statistics for a given text string."""
    words = text.split()
    return {
        "characters": len(text),
        "words": len(words),
        "sentences": text.count(".") + text.count("!") + text.count("?"),
        "uppercase": sum(1 for c in text if c.isupp…
14 0 Open
Strings & text easy

Text Processor Functions for Beginners in Python

Demonstrates simple text-processing utilities: word counting, word reversal, whitespace normalization, and lowercase conversion using basic string methods.

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

def reverse_words(text):
    """Return the text with words in reverse order."""
    return ' '.join(text.split()[::-1])

def remove_extra_spaces(text):
    """Return text with extra whitespace collapsed to a single s…
13 0 Open
Strings & text easy

Validate email format with regex in Python

A Python function using a regex pattern to validate simple email formats, returning True or False for each input.

regex email validation
Python
import re

def is_valid_email(email):
    pattern = r'^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}$'
    return bool(re.match(pattern, email))

if __name__ == "__main__":
    test_emails = [
        "user@example.com",
        "first.last@sub.domain.org",
        "invalid-email",
        "user@.com",
        "user@…
12 0 Open
Lists & loops easy

Check if List is Sorted Ascending in Python

Verify that a list is sorted in ascending order using the all() function and a generator expression.

lists sorted all
Python
def is_sorted_ascending(lst):
    return all(lst[i] <= lst[i + 1] for i in range(len(lst) - 1))

if __name__ == "__main__":
    test_lists = [
        [1, 2, 3, 4, 5],
        [1, 3, 2, 4, 5],
        [5, 4, 3, 2, 1],
        [1, 1, 2, 2, 3],
        [10],
        []
    ]
    for lst in test_lists:
        print(f"{l…
19 0 Open
Lists & loops easy

Compare Two Lists in Python: Common, Only in First, Only in Second

A beginner-friendly helper that loops over two lists and returns items common to both, items only in the first list, and items only in the second list.

lists comparison loops
Python
def compare_lists(list1, list2):
    common = []
    only_in_first = []
    only_in_second = []
    
    for item in list1:
        if item in list2:
            common.append(item)
        else:
            only_in_first.append(item)
    
    for item in list2:
        if item not in list1:
            only_in_second…
15 0 Open
Lists & loops easy

Convert a List of Integers to a Comma-Separated String in Python

Convert a list of integers into a single comma-separated string using a generator expression and str.join.

join list comma
Python
def ints_to_comma_string(numbers):
    return ",".join(str(num) for num in numbers)

if __name__ == "__main__":
    numbers = [1, 2, 3, 4, 5]
    result = ints_to_comma_string(numbers)
    print(result)
15 0 Open
Lists & loops easy

Find All Occurrences of an Item in a Python List

Loop through a list with enumerate() to collect the index of every match for a target value.

list enumerate loops
Python
def find_all(data, target):
    """Return indices of every occurrence of target in a list."""
    indices = []
    for index, item in enumerate(data):
        if item == target:
            indices.append(index)
    return indices


if __name__ == "__main__":
    sample = [10, 20, 30, 20, 40, 20, 50]
    target_value …
14 0 Open
Lists & loops easy

Find Duplicate Elements in a Python List

Identifies and returns duplicate elements from a Python list using sets for efficient membership tests.

duplicates sets list
Python
def find_duplicates(lst):
    seen = set()
    duplicates = set()
    for item in lst:
        if item in seen:
            duplicates.add(item)
        else:
            seen.add(item)
    return list(duplicates)

if __name__ == "__main__":
    sample = [1, 2, 3, 2, 4, 1, 5, 3]
    print(find_duplicates(sample))
12 0 Open
Lists & loops easy

Find Local Minima (Valleys) in a Numeric List in Python

This code finds indices of all local minima (valleys) in a numeric list, including edge cases, using a simple loop that compares each element with its neighbors.

local minima valleys list
Python
def find_local_minima(numbers):
    """Find indices of local minima (valleys) in a numeric list.
    
    A value is a local minimum if it's less than or equal to its neighbors.
    Edge elements are considered minima if they're less than or equal to their single neighbor.
    """
    if not numbers:
        return []…
14 0 Open
Lists & loops easy

Find Maximum Value in a List of Numbers in Python

Iterate through a list with a for loop to manually find and return the maximum numeric value.

max list loop
Python
def find_max(numbers):
    """Return the maximum value in a list of numbers."""
    if not numbers:
        return None
    max_value = numbers[0]
    for num in numbers[1:]:
        if num > max_value:
            max_value = num
    return max_value

if __name__ == "__main__":
    sample_list = [3, 7, 2, 15, 9, 11]
…
15 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.