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Python Code Samples

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

1055 matches
Strings & text easy

How to Escape HTML in Python

This code demonstrates how to use Python's `html.escape` function to safely encode user input for display in HTML, preventing XSS attacks.

html escaping security
Python
import html

def escape_user_input(user_input: str) -> str:
    """Escape HTML-sensitive characters for safe display."""
    return html.escape(user_input)

if __name__ == "__main__":
    sample_user_input = '<script>alert("XSS")</script> & \'quotes\''
    safe_output = escape_user_input(sample_user_input)
    print("…
13 0 Open
Strings & text easy

How to Extract Digits Only from a String in Python

This code uses a regular expression to remove all non-digit characters from a mixed string, returning only the digits.

regex string manipulation data cleaning
Python
import re

def extract_digits(text):
    """Return only the digits from the given text as a string."""
    return re.sub(r'\D', '', text)

if __name__ == "__main__":
    mixed = "abc123def456!@#789"
    result = extract_digits(mixed)
    print(result)
12 0 Open
Strings & text easy

How to Filter Text to Only Letters, Numbers, and Spaces in Python

A beginner-friendly function that filters a string to keep only alphabetic characters, digits, and spaces, removing punctuation and symbols.

text-filtering strings beginner
Python
def filter_text(text, keep_alpha=True, keep_digits=True, keep_spaces=True):
    allowed = set()
    if keep_alpha:
        allowed.update("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
    if keep_digits:
        allowed.update("0123456789")
    if keep_spaces:
        allowed.add(" ")
    return "".join(ch f…
11 0 Open
Strings & text easy

How to Filter a List of Strings by Keyword in Python

A helper function filters a list of strings by a keyword search with optional case sensitivity.

string filter list
Python
def filter_strings(items, keyword, case_sensitive=False):
    """
    Filter a list of strings by a keyword.
    
    Args:
        items: list of strings to filter
        keyword: substring to search for
        case_sensitive: if True, match case exactly
    
    Returns:
        list of strings containing the keyw…
12 0 Open
Strings & text easy

How to Format Strings with Named Placeholders in Python

Format a template string using named placeholders with the str.format() method and a dictionary.

string format placeholders
Python
def format_named(template, data):
    """Format a template string using named placeholders."""
    return template.format(**data)


if __name__ == "__main__":
    template = "Hello {name}, you are {age} years old and live in {city}."
    data = {"name": "Alice", "age": 30, "city": "London"}
    result = format_named(t…
15 0 Open
Strings & text easy

How to Format Text in Python

A beginner-friendly helper that cleans and changes the case of a string, with options for title, upper, lower, and capitalize.

string formatting case
Python
def format_text(text, case="title", strip_whitespace=True, remove_extra_spaces=True):
    """
    Formats a string based on common beginner needs.
    
    Args:
        text: Input string to format
        case: "title", "upper", "lower", or "capitalize"
        strip_whitespace: Remove leading/trailing whitespace
  …
12 0 Open
Strings & text easy

How to Format Text in Python (Beginner's Guide)

This beginner-friendly Python script demonstrates text formatting basics: stripping whitespace, converting to title case, replacing substrings, splitting into words, and generating a snippet.

string-manipulation text-formatting beginner
Python
text = "  hello world, welcome to python skillset!  "
cleaned = text.strip()
title_cased = cleaned.title()
replaced = title_cased.replace("Python", "PYTHON")
words = replaced.split()
word_count = len(words)
first_three = " ".join(words[:3])
snippet = first_three + "..."
print("Original:", repr(text))
print("Stripped:"…
13 0 Open
Strings & text easy

How to Format a Float as Currency in Python

This code defines a function that converts a float to a string formatted as US currency with two decimal places and comma separators.

formatting currency f-string
Python
def format_currency(amount):
    return f"${amount:,.2f}"

if __name__ == "__main__":
    test_amounts = [1234.5, 0, 9999999.999, -42.867]
    for amount in test_amounts:
        print(f"{amount} -> {format_currency(amount)}")
13 0 Open
Strings & text easy

How to Generate Initials from a Full Name in Python

Extract and uppercase the first letter of each word in a full name to produce initials using standard string methods.

strings initialism text-processing
Python
def generate_initials(full_name):
    parts = full_name.strip().split()
    initials = ''.join(part[0].upper() for part in parts if part)
    return initials

if __name__ == "__main__":
    name = "john f. kennedy"
    print(generate_initials(name))
14 0 Open
Strings & text easy

How to Generate Text Helper Functions in Python

Three simple Python functions that repeat, join, and count characters in strings for beginners.

strings text-processing functions
Python
def repeat_text(text, times):
    """Repeat a string a given number of times."""
    return text * times


def join_words(words, separator=" "):
    """Join a list of words into a single string."""
    return separator.join(words)


def count_characters(text):
    """Count character occurrences in a string."""
    ret…
14 0 Open
Strings & text easy

How to Group Data by Category in Python

Group a list of (category, value) tuples into a dictionary of lists using the setdefault method.

grouping dictionaries setdefault
Python
def group_by_category(data):
    """Group list of (category, value) tuples into dictionaries of lists."""
    groups = {}
    for category, value in data:
        groups.setdefault(category, []).append(value)
    return groups

if __name__ == "__main__":
    items = [
        ("fruit", "apple"),
        ("veg", "carro…
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 Inspect String Statistics in Python

A beginner-friendly function that returns detailed statistics about a string, including length, word count, character types, and easy text transformations.

strings text-analysis statistics
Python
def inspect_text(text: str) -> dict:
    """Return useful stats about a string for beginners."""
    words = text.split()
    return {
        "length": len(text),
        "word_count": len(words),
        "uppercase": sum(1 for ch in text if ch.isupper()),
        "lowercase": sum(1 for ch in text if ch.islower()),
 …
14 0 Open
Strings & text easy

How to Join List of Words into a Sentence in Python

Concatenate a list of strings into a single sentence with spaces using the Python string join() method.

string join list
Python
words = ["Hello", "world", "this", "is", "Python"]
sentence = " ".join(words)
print(sentence)
15 0 Open
Strings & text easy

How to Join Multiline Text with a Semicolon Separator in Python

This code joins non-empty lines of multiline text into a single string separated by semicolons, stripping leading and trailing whitespace from each line.

multiline join separator
Python
def join_multiline_text_with_semicolon(text):
    """Join lines of multiline text with a semicolon separator."""
    lines = [line.strip() for line in text.splitlines() if line.strip()]
    return "; ".join(lines)


if __name__ == "__main__":
    sample_text = """First line
Second line
Third line"""
    result = join_…
13 0 Open
Strings & text easy

How to Mask Credit Card Middle Digits in Python

Mask the middle digits of credit card numbers in a string, keeping only the first 8 and last 4 digits, using regular expressions.

regex string-manipulation security
Python
import re

def mask_credit_card(text: str) -> str:
    pattern = re.compile(r'(\d{4}[-\s]?)(\d{4}[-\s]?)(\d{4}[-\s]?)(\d{4})')
    return pattern.sub(lambda m: m.group(1) + m.group(2) + '****' + m.group(4), text)

if __name__ == "__main__":
    sample = "Card: 1234-5678-9012-3456 and 1111 2222 3333 4444"
    print(mas…
13 0 Open
Strings & text easy

How to Merge Strings in Python

Merge multiple strings or a list of text lines into one string with a custom separator

strings join merging
Python
def merge_strings(*parts, separator=" "):
    """Merge multiple string parts into one string with a separator."""
    return separator.join(parts)


def merge_text_lines(lines, separator="\n"):
    """Merge a list of text lines into a single string."""
    return separator.join(lines)


if __name__ == "__main__":
    …
15 0 Open
Strings & text easy

How to Merge Two Strings Character by Character in Python

Interleave characters from two strings, appending any surplus characters from the longer string at the end.

strings merge interleave
Python
def merge_texts(left: str, right: str) -> str:
    """
    Merges two strings by interleaving their characters:
    first char from left, first from right, then second from left,
    second from right, and so on. If one string is longer, the
    remaining characters are appended at the end.

    Example:
    merge_tex…
14 0 Open
Strings & text easy

How to Normalize Text in Python

This code defines a function that trims, lowercases, and collapses extra whitespace in a string, returning normalized text.

string normalization whitespace
Python
def normalize_text(text: str) -> str:
    normalized = " ".join(text.lower().strip().split())
    return normalized


if __name__ == "__main__":
    raw = "   Hello,   WORLD!   This is   a  test.   "
    print(normalize_text(raw))
14 0 Open
Strings & text easy

How to Pad a String with Zeros in Python

Pad a string to a fixed width by left-filling it with zeros using the built-in str.zfill method.

strings padding zfill
Python
def pad_zeros(s, width):
    return s.zfill(width)

if __name__ == "__main__":
    print(repr(pad_zeros("42", 6)))
    print(repr(pad_zeros("-7", 5)))
    print(repr(pad_zeros("hello", 10)))
    print(repr(pad_zeros("123", 3)))
16 0 Open
Strings & text easy

How to Parse and Clean Text in Python

This code defines three helper functions to parse text into lowercase words, count unique word frequencies, and clean text by removing punctuation and extra whitespace.

text parsing string cleaning word frequency
Python
def extract_words(text: str) -> list[str]:
    """Return a list of lowercase words from the given text."""
    return [word.lower() for word in text.split() if word.isalpha()]


def count_unique_words(text: str) -> dict[str, int]:
    """Return a dictionary with unique words and their frequencies."""
    words = extra…
11 0 Open
Strings & text easy

How to Partition a String on the First Delimiter in Python

Split a string into a tuple of (before, delimiter, after) at the first occurrence of a given delimiter, using a custom function or the built-in str.partition.

string partition split
Python
def partition_string(s, delimiter):
    """Split string into (before, delimiter, after) on the first occurrence."""
    for i, ch in enumerate(s):
        if ch == delimiter:
            return s[:i], ch, s[i+1:]
    return s, "", ""


if __name__ == "__main__":
    # Single-character delimiter
    s1 = "hello,world,h…
13 0 Open
Strings & text easy

How to Process Lines of Text in Python

Strip whitespace, split a multi-line string, count words per line, and print structured summaries using basic string methods and loops.

strings text-processing splitlines
Python
text = """   Python is great!
Coding is fun.
   Python skills help you grow.   """

lines = text.strip().splitlines()
line_count = len(lines)

processed = []
for line in lines:
    stripped = line.strip()
    word_count = len(stripped.split())
    processed.append({
        "original": line,
        "stripped": stripp…
13 0 Open
Strings & text easy

How to Process Text in Python

This code processes multiline text by splitting lines, stripping whitespace, counting words and characters, and converting to lowercase.

text-processing strings beginner
Python
def process_text(text):
    lines = text.split("\n")
    clean_lines = []
    for line in lines:
        stripped = line.strip()
        if stripped:
            tokens = stripped.split()
            title_case = stripped.lower()
            clean_lines.append({
                "raw": stripped,
                "word_c…
12 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.