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Python Code Samples

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

3 matches
Comprehensions & generators easy

How to Create a Pairwise Generator with zip and tee in Python

Build a memory-efficient generator that yields successive overlapping pairs from any iterable using zip and tee.

itertools generators zip
Python
from itertools import tee


def pairwise(iterable):
    """Yield successive overlapping pairs from iterable."""
    a, b = tee(iterable)
    next(b, None)
    return zip(a, b)


if __name__ == "__main__":
    values = [1, 2, 3, 4, 5]
    print(list(pairwise(values)))
    print(list(pairwise("hello")))
15 0 Open
Streaming & messaging easy

Exactly Once Idempotent Consumer Store in Python

A mock key-value store that guarantees exactly-once processing by rejecting duplicate message keys in a message or event stream.

idempotency streaming deduplication
Python
from collections import defaultdict

class ExactlyOnceStore:
    def __init__(self):
        self.processed = defaultdict(set)
        self.data = {}

    def consume(self, key, value):
        if key in self.data:
            return False
        self.data[key] = value
        return True

    def get_processed_count…
15 0 Open
Reliability & rate limiting easy

Exactly Once Processing Dedupe Mock in Python

Implements a streaming deduplicator using a set and queue to guarantee each item is processed exactly once while preserving insertion order.

deduplication exactly-once streaming
Python
from collections import deque

class DedupeStream:
    def __init__(self):
        self.seen = set()
        self.queue = deque()

    def add(self, item):
        if item not in self.seen:
            self.seen.add(item)
            self.queue.append(item)
            print(f"Processed: {item} (exactly once)")
      …
15 0 Open

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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.