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Python Code Samples

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

6 matches
Strings & text easy

How to Check and Manipulate Strings in Python

Demonstrates core string inspection and transformation methods like case conversion, trimming, splitting, and membership checks on a sample string.

strings text-processing beginners
Python
text = "  Hello, Python Learners!  "

print(f"Original: '{text}'")
print(f"Lowercase: '{text.lower()}'")
print(f"Uppercase: '{text.upper()}'")
print(f"Title case: '{text.title()}'")
print(f"Stripped: '{text.strip()}'")
print(f"Length: {len(text)}")
print(f"Replace: '{text.replace('Python', 'Programming')}'")
print(f"S…
15 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
Dictionaries & sets easy

How to Check if a Set is a Subset in Python

Check whether one set contains all elements of another set using the issubset method.

set subset membership
Python
def is_subset(allowed_set, check_set):
    """
    Check if check_set is a subset of allowed_set.
    Returns True if all elements of check_set are in allowed_set, otherwise False.
    """
    return check_set.issubset(allowed_set)

if __name__ == "__main__":
    # Example usage
    allowed = {1, 2, 3, 4, 5}
    valid…
17 0 Open
Dictionaries & sets easy

How to Find Symmetric Difference Between Two Python Sets

Compute elements unique to each set and build a flag dictionary showing membership across two Python sets.

sets set-operations symmetric-difference
Python
def symmetric_difference_with_flags(set_a, set_b):
    """Return elements in either set but not both, grouped by which set they came from."""
    only_in_a = set_a - set_b
    only_in_b = set_b - set_a
    
    print(f"Only in A: {only_in_a}")
    print(f"Only in B: {only_in_b}")
    print(f"Symmetric difference: {onl…
13 0 Open
Algorithms & data structures easy

Find Elements in One Python List but Not Another

Return a new list containing only the elements from list A that are not present in list B, preserving duplicates and order.

list difference set membership filtering
Python
def difference_elements(a, b):
    """Return elements present in list a but not in list b."""
    set_b = set(b)
    return [item for item in a if item not in set_b]

if __name__ == "__main__":
    a = [1, 2, 3, 4, 5, 3, 2]
    b = [2, 4, 6]
    result = difference_elements(a, b)
    print(f"A: {a}")
    print(f"B: {b…
14 0 Open
Algorithms & data structures easy

How to Remove Duplicates in Python Preserving Order

Removes duplicate items from a list while keeping the first occurrence order intact using a set for fast membership checks.

deduplication set list
Python
def remove_duplicates_preserving_order(items):
    seen = set()
    result = []
    for item in items:
        if item not in seen:
            seen.add(item)
            result.append(item)
    return result

if __name__ == "__main__":
    sample = [3, 1, 2, 1, 3, 4, 2, 5]
    unique_items = remove_duplicates_preserv…
14 0 Open

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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.