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Data pipelines & processing

ETL-style flows, batch transforms, validation, and moving data between formats.

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Data pipelines & processing easy

How to Deduplicate Events with At-Least-Once Delivery in Python

Implements an exactly-once processing pattern for at-least-once event delivery by tracking seen event IDs in a set, skipping duplicates.

deduplication idempotent event-processing
Python 
seen_ids = set()

def process_event(event_id: str, payload: dict) -> dict:
    """Process an event exactly once, ignoring duplicates."""
    if event_id in seen_ids:
        return {"status": "duplicate", "event_id": event_id}
    seen_ids.add(event_id)
    return {"status": "processed", "event_id": event_id, **payloa…
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