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Python Code Samples

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

4 matches
Lists & loops easy

How to Calculate the Sum of List Elements in Python

Iterates over a list with a for loop, accumulates each number into a total variable, and returns the sum of all elements.

sum list loop
Python 
def sum_list_elements(numbers):
    """Return the sum of all elements in a list."""
    total = 0
    for num in numbers:
        total += num
    return total

if __name__ == "__main__":
    sample_list = [1, 2, 3, 4, 5]
    result = sum_list_elements(sample_list)
    print(f"The sum of {sample_list} is {result}")
13 0 Open
Comprehensions & generators easy

How to Accumulate Values with a Generator in Python

This generator yields the running total of an iterable's elements, producing a cumulative sum with each step.

generator accumulate cumulative-sum
Python 
def accum(iterable):
    total = 0
    for item in iterable:
        total += item
        yield total

# Demo
if __name__ == "__main__":
    data = [1, 2, 3, 4, 5]
    print(list(accum(data)))  # [1, 3, 6, 10, 15]

    # Also works with any iterable, e.g., range
    print(list(accum(range(1, 6))))  # [1, 3, 6, 10, 15]
14 0 Open
AI & LLM integration patterns easy

How to Accumulate Streamed Tokens into a Final String in Python

Accumulate a stream of tokens into a single final string by concatenating each token in sequence.

streaming tokens strings
Python 
def accumulate_tokens(tokens):
    """Accumulate a stream of tokens into a single final string."""
    result = ""
    for token in tokens:
        result += token
    return result


if __name__ == "__main__":
    token_stream = ["Hello", ", ", "world", "!", " This ", "is ", "accumulated."]
    final_string = accumul…
16 0 Open
System design patterns easy

How to Take Periodic Snapshots of Aggregate State in Python

Build a Python class that accumulates values and periodically captures immutable snapshots of total, count, and average for later analysis.

aggregation snapshots state-management
Python 
import time
import random
from collections import defaultdict


class SnapshotAggregator:
    def __init__(self):
        self.total = 0
        self.count = 0
        self.history = []

    def add(self, value):
        self.total += value
        self.count += 1

    def snapshot(self):
        avg = self.total / se…
12 0 Open

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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

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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.

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