PJ API: Remove places with duplicated merchant_id from results

[amatissart]

It has been noticed that different result pages from the API may contain duplicated POIs.

This PR suggests to remove these duplicated items. As a result, the number of places in the response, may be strictly less than the requested "size", even if more places would have been available in following pages.

[remi-dupre]

I was wondering if there was a more declarative way to do it. I don't really think it is better (especially with black enforcing it as a one-liner) but still funny 🤩

EDIT: with a small difference since it is the order of the last occurrence that would be preserved

Suggested change

	merchant_ids = set()
	places = []
	for p in api_places:
	merchant_id = p.data.merchant_id
	if merchant_id not in merchant_ids:
	places.append(p)
	if merchant_id:
	merchant_ids.add(merchant_id)
	return places
	return list({place.data.merchant_id: place for place in api_places}.values())

[bbecquet]

I was looking for something similar but discarded it because I thought the order was lost in a dictionary… but apparently since Python 3.7 it is not.

Actually I hoped to find something as elegant as Ramda.uniqBy :)

[amatissart]

I agree that writing 9 lines for this does not look satisfying. But the one-liner would require a double reversed to keep the first occurrence, and it also collapses None keys (they are not supposed to exist, but are not duplicates per se).