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Python Code Samples

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

10 matches
Strings & text easy

How to Check Palindrome in Python (Ignore Case and Spaces)

Check whether a string is a palindrome while ignoring case, spaces, and all non-alphanumeric characters using Python's filter and string reversal.

palindrome string case-insensitive
Python
def is_palindrome(text: str) -> bool:
    cleaned = ''.join(char.lower() for char in text if char.isalnum())
    return cleaned == cleaned[::-1]

if __name__ == "__main__":
    test_cases = [
        "A man, a plan, a canal: Panama",
        "race a car",
        "Was it a car or a cat I saw?",
        "hello",
      …
13 0 Open
Strings & text easy

How to Check if a String Ends with a File Extension in Python

This code checks whether a filename ends with any of a list of file extensions, handling case insensitivity.

file-extension string-methods endswith
Python
def ends_with_extension(filename, extensions):
    """Check if a filename ends with any of the given extensions."""
    lower_name = filename.lower()
    return any(lower_name.endswith(ext.lower()) for ext in extensions)

if __name__ == "__main__":
    # Test cases
    test_files = ["report.pdf", "image.PNG", "script.…
16 0 Open
Strings & text easy

How to Check if a String Starts With a Prefix Case-Insensitively in Python

This code defines a function that checks if a string starts with a given prefix, ignoring case, using the lower() method.

string-methods case-insensitive startswith
Python
def starts_with_case_insensitive(text, prefix):
    """Check if a string starts with a given prefix, ignoring case."""
    return text.lower().startswith(prefix.lower())


if __name__ == "__main__":
    test_strings = [
        ("Hello World", "hello"),
        ("Python Programming", "PYTHON"),
        ("Data Science"…
14 0 Open
Strings & text easy

How to Compare Two Strings in Python

Compares two string values and returns a detailed report with equality, case-insensitive comparison, lengths, and uppercase versions.

string-comparison case-insensitive helper-function
Python
def compare_data(first_value, second_value):
    """Compare two string values and return a report."""
    if first_value == second_value:
        status = "MATCH"
    else:
        status = "DIFFER"
    return {
        "first_value": first_value,
        "second_value": second_value,
        "status": status,
       …
12 0 Open
Strings & text easy

How to Highlight Search Terms in Python Text

Highlights all case-insensitive occurrences of a search term in a string by wrapping them in markers.

string search highlight
Python
def highlight_search_term(text: str, term: str) -> str:
    """Highlight all occurrences of term in text using terminal-style markers."""
    if not term:
        return text

    term_lower = term.lower()
    result = []
    i = 0

    while i < len(text):
        # Check if the term starts at position i (case-insens…
11 0 Open
Strings & text easy

How to Sort Text Alphabetically in Python

Sort words or lines alphabetically with case-insensitive ordering while preserving original casing.

sorting text-processing strings
Python
def sort_words(text):
    """Sort words alphabetically (case-insensitive), preserving case."""
    words = text.split()
    return sorted(words, key=str.lower)


def sort_lines(text):
    """Sort lines alphabetically (case-insensitive), preserving case."""
    lines = [line for line in text.splitlines() if line.strip(…
11 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 <…
11 0 Open
Files & data easy

Create a Personal Knowledge Base That Searches Notes Instantly in Python

Build a lightweight personal knowledge base with JSON storage and instant case-insensitive full-text search across note titles and content.

json knowledge base search
Python
import json
import re
import sys

class PersonalKnowledgeBase:
    def __init__(self, file_path="kb_notes.json"):
        self.file_path = file_path
        self.notes = self._load_notes()

    def _load_notes(self):
        try:
            with open(self.file_path, "r") as f:
                return json.load(f)
    …
54 0 Open
Dictionaries & sets medium

Build a Case-Insensitive Dict with a Wrapper Class in Python

Create a custom dict subclass that treats keys as case-insensitive by normalizing them to lowercase, with a full set of common dict methods.

dictionary case-insensitive wrapper
Python
class CaseInsensitiveDict:
    def __init__(self, data=None):
        self._data = {}
        if data:
            self.update(data)

    def __setitem__(self, key, value):
        self._data[str(key).lower()] = value

    def __getitem__(self, key):
        return self._data[str(key).lower()]

    def __delitem__(sel…
13 0 Open
Dictionaries & sets easy

How to Sort Dictionary Keys Alphabetically in Python

This code returns a list of dictionary keys sorted alphabetically, using a case-insensitive comparison while preserving the original insertion order for keys that are equal.

sorting dictionary case-insensitive
Python
data = {
    "banana": 3,
    "apple": 1,
    "Cherry": 5,
    "date": 2,
    "apple": 4,
    "Fig": 6,
    "banana": 2,
}

def sort_dict_keys_alphabetically(d):
    """Return a list of keys sorted alphabetically (case-insensitive), stable for duplicates."""
    return sorted(d.keys(), key=lambda k: k.lower())

if __n…
10 0 Open

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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.