How to Deduplicate Events in Python with SHA256 Hashing

```python
import hashlib
import json
from collections import defaultdict


class EventDeduplicator:
    def __init__(self):
        self.seen_hashes = set()
        self.duplicate_counts = defaultdict(int)

    def process_event(self, event):
        event_key = f"{event['event_id']}:{event['timestamp']}"
        event_hash = hashlib.sha256(event_key.encode()).hexdigest()

        if event_hash in self.seen_hashes:
            self.duplicate_counts[event["event_type"]] += 1
            return False
        self.seen_hashes.add(event_hash)
        return True

    def get_duplicate_stats(self):
        return dict(self.duplicate_counts)


if __name__ == "__main__":
    deduplicator = EventDeduplicator()

    mock_events = [
        {"event_id": "evt_001", "event_type": "message", "timestamp": 1719000000, "data": "Hello"},
        {"event_id": "evt_002", "event_type": "message", "timestamp": 1719000001, "data": "World"},
        {"event_id": "evt_001", "event_type": "message", "timestamp": 1719000000, "data": "Hello"},
        {"event_id": "evt_003", "event_type": "notification", "timestamp": 1719000002, "data": "Alert"},
        {"event_id": "evt_003", "event_type": "notification", "timestamp": 1719000002, "data": "Alert"},
    ]

    processed = []
    for event in mock_events:
        if deduplicator.process_event(event):
            processed.append(event)

    print(f"Processed: {len(processed)} unique events")
    print(f"Duplicates: {deduplicator.get_duplicate_stats()}")
    print(json.dumps(processed, indent=2))