Network Delay Time LeetCode solution in Python

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import heapq
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class Solution:
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    def networkDelayTime(self, times: List[List[int]], n: int, k: int) -> int:
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        adjlist = [[] for _ in range(n + 1)]
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        for src, dst, weight in times:
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            adjlist[src].append((dst, weight))
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        visited = [-1] * (n + 1)
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        captured = [-1] * (n + 1)
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        priority_queue = [(0, k)]
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        nums = 0
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        total_dist = 0
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        while priority_queue:
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            dst, node = heapq.heappop(priority_queue)
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            if captured[node] != -1:
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                continue
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            captured[node] = dst
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            nums += 1
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            total_dist = dst
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            for nbr, wt in adjlist[node]:
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                if captured[nbr] == -1:
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                    heapq.heappush(priority_queue, (captured[node] + wt, nbr))
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        if nums == n:
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            return total_dist
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        else:
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            return -1