Buggy python submission (verdict: Runtime Error):
import sys
import math
from collections import deque
import heapq as hq

sys.setrecursionlimit(1000000)
MOD = 10 ** 9 + 7
input = lambda: sys.stdin.readline().strip()
NI = lambda: int(input())
NMI = lambda: map(int, input().split())
NLI = lambda: list(NMI())
SI = lambda: input()


def make_grid(h, w, num): return [[int(num)] * w for _ in range(h)]


def main():
    T = NI()
    for _ in range(T):
        N = NI()
        camels = [NLI() for _ in range(N)]
        base = 0
        camels_L = [[] for _ in range(N+1)]
        camels_R = [[] for _ in range(N+1)]
        # 左から詰めるラクダと右から詰めるラクダを仕分ける
        for camel in camels:
            if camel[1] >= camel[2]:
                camels_L[camel[0]].append(camel[1] - camel[2])
                base += camel[2] # LとRの低いほうを加算
            else:
                camels_R[N - camel[0]].append(camel[2] - camel[1])
                base += camel[1] # LとRの低いほうを加算
        ans = 0
        heap_camels = []
        hq.heapify(heap_camels)
        for i in range(1, N+1):
            for camel in camels_L[i]:
                hq.heappush(heap_camels, camel)
            while len(heap_camels) > i:
                hq.heappop()
        if heap_camels:
            ans += sum(heap_camels)

        heap_camels = []
        hq.heapify(heap_camels)
        for i in range(1, N+1):
            for camel in camels_R[i]:
                hq.heappush(heap_camels, camel)
            while len(heap_camels) > i:
                hq.heappop()
        if heap_camels:
            ans += sum(heap_camels)
        print(ans + base)



if __name__ == "__main__":
    main()

Fixed submission:
import sys
import math
from collections import deque
import heapq as hq

sys.setrecursionlimit(1000000)
MOD = 10 ** 9 + 7
input = lambda: sys.stdin.readline().strip()
NI = lambda: int(input())
NMI = lambda: map(int, input().split())
NLI = lambda: list(NMI())
SI = lambda: input()


def make_grid(h, w, num): return [[int(num)] * w for _ in range(h)]


def main():
    T = NI()
    for _ in range(T):
        N = NI()
        camels = [NLI() for _ in range(N)]
        base = 0
        camels_L = [[] for _ in range(N+1)]
        camels_R = [[] for _ in range(N+1)]
        # 左から詰めるラクダと右から詰めるラクダを仕分ける
        for camel in camels:
            if camel[1] >= camel[2]:
                camels_L[camel[0]].append(camel[1] - camel[2])
                base += camel[2] # LとRの低いほうを加算
            else:
                camels_R[N - camel[0]].append(camel[2] - camel[1])
                base += camel[1] # LとRの低いほうを加算
        ans = 0
        heap_camels = []
        hq.heapify(heap_camels)
        for i in range(1, N+1):
            for camel in camels_L[i]:
                hq.heappush(heap_camels, camel)
            while len(heap_camels) > i:
                hq.heappop(heap_camels)
        if heap_camels:
            ans += sum(heap_camels)

        heap_camels = []
        hq.heapify(heap_camels)
        for i in range(1, N+1):
            for camel in camels_R[i]:
                hq.heappush(heap_camels, camel)
            while len(heap_camels) > i:
                hq.heappop(heap_camels)
        if heap_camels:
            ans += sum(heap_camels)
        print(ans + base)



if __name__ == "__main__":
    main()

Buggy python submission (verdict: Runtime Error):
import sys
import math
from collections import deque
import heapq as hq

sys.setrecursionlimit(1000000)
MOD = 10 ** 9 + 7
input = lambda: sys.stdin.readline().strip()
NI = lambda: int(input())
NMI = lambda: map(int, input().split())
NLI = lambda: list(NMI())
SI = lambda: input()


def make_grid(h, w, num): return [[int(num)] * w for _ in range(h)]


def main():
    T = NI()
    A = []
    for _ in range(T):
        N = NI()
        camels = [NLI() for _ in range(N)]
        base = 0
        camels_L = [[] for _ in range(N+1)]
        camels_R = [[] for _ in range(N+1)]
        # 左から詰めるラクダと右から詰めるラクダを仕分ける
        for camel in camels:
            if camel[1] >= camel[2]:
                camels_L[camel[0]].append(camel[1] - camel[2])
                base += camel[2] # LとRの低いほうを加算
            else:
                camels_R[N - camel[0]].append(camel[2] - camel[1])
                base += camel[1] # LとRの低いほうを加算
        ans = 0
        heap_camels = []
        hq.heapify(heap_camels)
        for i in range(1, N+1):
            for camel in camels_L[i]:
                hq.heappush(heap_camels, camel)
            while len(heap_camels) > i:
                hq.heappop()
        ans += sum(heap_camels)

        heap_camels = []
        hq.heapify(heap_camels)
        for i in range(1, N+1):
            for camel in camels_R[i]:
                hq.heappush(heap_camels, camel)
            while len(heap_camels) > i:
                hq.heappop()
        ans += sum(heap_camels)
        print(ans + base)



if __name__ == "__main__":
    main()

Fixed submission:
import sys
import math
from collections import deque
import heapq as hq

sys.setrecursionlimit(1000000)
MOD = 10 ** 9 + 7
input = lambda: sys.stdin.readline().strip()
NI = lambda: int(input())
NMI = lambda: map(int, input().split())
NLI = lambda: list(NMI())
SI = lambda: input()


def make_grid(h, w, num): return [[int(num)] * w for _ in range(h)]


def main():
    T = NI()
    for _ in range(T):
        N = NI()
        camels = [NLI() for _ in range(N)]
        base = 0
        camels_L = [[] for _ in range(N+1)]
        camels_R = [[] for _ in range(N+1)]
        # 左から詰めるラクダと右から詰めるラクダを仕分ける
        for camel in camels:
            if camel[1] >= camel[2]:
                camels_L[camel[0]].append(camel[1] - camel[2])
                base += camel[2] # LとRの低いほうを加算
            else:
                camels_R[N - camel[0]].append(camel[2] - camel[1])
                base += camel[1] # LとRの低いほうを加算
        ans = 0
        heap_camels = []
        hq.heapify(heap_camels)
        for i in range(1, N+1):
            for camel in camels_L[i]:
                hq.heappush(heap_camels, camel)
            while len(heap_camels) > i:
                hq.heappop(heap_camels)
        if heap_camels:
            ans += sum(heap_camels)

        heap_camels = []
        hq.heapify(heap_camels)
        for i in range(1, N+1):
            for camel in camels_R[i]:
                hq.heappush(heap_camels, camel)
            while len(heap_camels) > i:
                hq.heappop(heap_camels)
        if heap_camels:
            ans += sum(heap_camels)
        print(ans + base)



if __name__ == "__main__":
    main()