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Strings & text

Format, split, join, parse, and clean text — everyday Python string patterns.

12 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 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 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 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 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
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 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: 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

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

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Strings & text — Python code examples

What you will find here

This page collects strings & text snippets — short, copy-ready Python you can paste into our free online IDE and run without installing anything. Each sample includes a plain-English explanation and the full source code.

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.