Design a Food Rating System LeetCode solution in Python

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from heapq import heapify, heappop, heappush
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class RatedFood:
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    def __init__(self, rating, food):
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        self.rating = rating
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        self.food = food
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    def __lt__(self, other):
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        if other.rating == self.rating:
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            return self.food < other.food
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        return self.rating < other.rating
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class FoodRatings:
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    def __init__(self, foods: List[str], cuisines: List[str], ratings: List[int]):
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        self.cuis_to_score_heap = defaultdict(list)
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        self.food_to_latest_ratings = defaultdict(int)
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        self.food_to_cuis = defaultdict(str)
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        for food, cuis, rating in zip(foods, cuisines, ratings):
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            self.food_to_cuis[food] = cuis
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            self.food_to_latest_ratings[food] = rating
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            heappush(self.cuis_to_score_heap[cuis], RatedFood(-rating, food))
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    def changeRating(self, food: str, newRating: int) -> None:
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        self.food_to_latest_ratings[food] = newRating
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        cuis = self.food_to_cuis[food]
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        heappush(self.cuis_to_score_heap[cuis], RatedFood(-newRating, food))
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    def highestRated(self, cuisine: str) -> str:
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        while True:
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            ratedFood = heappop(self.cuis_to_score_heap[cuisine])
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            if self.food_to_latest_ratings[ratedFood.food] == (-ratedFood.rating):
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                # because the food item is still valid, we put it back into the heap
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                heappush(self.cuis_to_score_heap[cuisine], ratedFood)
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                return ratedFood.food