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Python Code Samples

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

9 matches
Strings & text easy

How to Convert and Process Text in Python

This code cleans, converts, splits, joins, counts, replaces, reverses, and finds substrings in a text string using Python's standard string methods.

strings text processing methods
Python
text = "  hello world, python is fun!  "

# Clean up whitespace
cleaned = text.strip()

# Convert to title case
titled = cleaned.title()

# Split into words
words = cleaned.split()

# Join with hyphens
hyphenated = "-".join(words)

# Count occurrences of a letter
letter_count = cleaned.count("o")

# Replace a word
rep…
11 0 Open
Strings & text easy

How to Sort Text in Python with a Simple Helper Function

A compact helper function that sorts a list of strings or splits a string into words and sorts them alphabetically, with optional reverse ordering.

sorting strings text-processing
Python
def sort_text(data, reverse=False):
    """
    Sort a list of strings (or a single string split into words) alphabetically.
    """
    if isinstance(data, str):
        words = data.split()
    else:
        words = [str(item) for item in data]
    return sorted(words, reverse=reverse)


if __name__ == "__main__":
 …
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

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
Lists & loops easy

How to Reverse a List in Place Without Using reverse() in Python

A two-pointer while loop swaps elements from both ends toward the center to reverse a list in place without creating a copy.

lists in-place two-pointer
Python
def reverse_list_in_place(lst):
    left = 0
    right = len(lst) - 1
    while left < right:
        lst[left], lst[right] = lst[right], lst[left]
        left += 1
        right -= 1


if __name__ == "__main__":
    my_list = [1, 2, 3, 4, 5]
    print("Original:", my_list)
    reverse_list_in_place(my_list)
    prin…
14 0 Open
Dictionaries & sets easy

How to Invert a Dictionary in Python Safely

Swap dictionary keys and values while detecting duplicate values to prevent silent data loss.

dictionary inversion data-safety
Python
def invert_dict_safely(d):
    inverted = {}
    for key, value in d.items():
        if value not in inverted:
            inverted[value] = key
        else:
            raise ValueError(f"Duplicate value '{value}' would cause data loss")
    return inverted


if __name__ == "__main__":
    sample = {"a": 1, "b": 2,…
15 0 Open
Algorithms & data structures easy

Find the Last Index Where a Condition Is True in Python

This code scans a sequence from the end and returns the index of the last element that satisfies a given condition, or -1 if none do.

search list reverse
Python
def last_index_where(sequence, condition):
    """Return the index of the last element in sequence that satisfies condition."""
    for i in range(len(sequence) - 1, -1, -1):
        if condition(sequence[i]):
            return i
    return -1

if __name__ == "__main__":
    numbers = [1, 4, 7, 2, 9, 5, 8, 3]
    is_…
12 0 Open
Automation & scripting easy

How to Sort Command-Line Arguments in Python

Build a beginner-friendly argparse CLI that sorts numbers or words passed as arguments, with an optional reverse flag.

argparse cli sorting
Python
import argparse


def main():
    parser = argparse.ArgumentParser(description="Sort numbers or words from the command line.")
    parser.add_argument("items", nargs="+", help="Items to sort (numbers or words)")
    parser.add_argument("--reverse", "-r", action="store_true", help="Sort in descending order")
    args =…
13 0 Open

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  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.