Buggy python submission (verdict: Time Limit Exceeded):
n, m, r = map(int,input().split())
R = list(map(int,input().split()))
A = [list(map(int,input().split())) for i in range(m)]

M = [[float("inf")] * (n+1) for i in range(n+1)]

for i in range(1, n+1):
    M[i][i] = 0
for i in range(m):
    M[A[i][0]][A[i][1]] = A[i][2]
    M[A[i][1]][A[i][0]] = A[i][2]

for k in range(1, n+1):
    for i in range(1, n+1):
        for j in range(i+1, n+1):
            if k <= i:
                M[i][j] = min(M[i][j], M[k][i] + M[k][j])
            elif k <= j:
                M[i][j] = min(M[i][j], M[i][k] + M[k][j])
            else:
                M[i][j] = min(M[i][j], M[i][j] + M[j][k])

# 上のコードだとTLE

# from scipy.sparse.csgraph import floyd_warshall
# M = floyd_warshall(M)

import itertools
R1 = list(itertools.permutations(R))

ans = float("inf")
for i in range(len(R1)):
    ans1 = 0
    for j in range(r-1):
        ans1 += M[R1[i][j]][R1[i][j+1]]
    ans = min(ans, ans1)

print(int(ans))


Fixed submission:
n, m, r = map(int,input().split())
R = list(map(int,input().split()))
A = [list(map(int,input().split())) for i in range(m)]

M = [[float("inf")] * (n+1) for i in range(n+1)]

for i in range(1, n+1):
    M[i][i] = 0
for i in range(m):
    M[A[i][0]][A[i][1]] = A[i][2]
    M[A[i][1]][A[i][0]] = A[i][2]

# for k in range(1, n+1):
#     for i in range(1, n+1):
#         for j in range(1, n+1):
#             M[i][j] = min(M[i][j], M[i][k] + M[k][j])

from scipy.sparse.csgraph import floyd_warshall
M = floyd_warshall(M)

import itertools
R1 = list(itertools.permutations(R))

ans = float("inf")
for i in range(len(R1)):
    ans1 = 0
    for j in range(r-1):
        ans1 += M[R1[i][j]][R1[i][j+1]]
    ans = min(ans, ans1)

print(int(ans))

Buggy python submission (verdict: Time Limit Exceeded):
n, m, r = map(int,input().split())
R = list(map(int,input().split()))
A = [list(map(int,input().split())) for i in range(m)]

M = [[float("inf")] * (n+1) for i in range(n+1)]

for i in range(1, n+1):
    M[i][i] = 0
for i in range(m):
    M[A[i][0]][A[i][1]] = A[i][2]
    M[A[i][1]][A[i][0]] = A[i][2]

for k in range(1, n+1):
    for i in range(1, n+1):
        for j in range(1, n+1):
            M[i][j] = min(M[i][j], M[i][k] + M[k][j])

# 上のコードだとTLE

# from scipy.sparse.csgraph import floyd_warshall
# M = floyd_warshall(M)

import itertools
R1 = list(itertools.permutations(R))

ans = float("inf")
for i in range(len(R1)):
    ans1 = 0
    for j in range(r-1):
        ans1 += M[R1[i][j]][R1[i][j+1]]
    ans = min(ans, ans1)

print(int(ans))


Fixed submission:
n, m, r = map(int,input().split())
R = list(map(int,input().split()))
A = [list(map(int,input().split())) for i in range(m)]

M = [[float("inf")] * (n+1) for i in range(n+1)]

for i in range(1, n+1):
    M[i][i] = 0
for i in range(m):
    M[A[i][0]][A[i][1]] = A[i][2]
    M[A[i][1]][A[i][0]] = A[i][2]

# for k in range(1, n+1):
#     for i in range(1, n+1):
#         for j in range(1, n+1):
#             M[i][j] = min(M[i][j], M[i][k] + M[k][j])

from scipy.sparse.csgraph import floyd_warshall
M = floyd_warshall(M)

import itertools
R1 = list(itertools.permutations(R))

ans = float("inf")
for i in range(len(R1)):
    ans1 = 0
    for j in range(r-1):
        ans1 += M[R1[i][j]][R1[i][j+1]]
    ans = min(ans, ans1)

print(int(ans))

Buggy python submission (verdict: Time Limit Exceeded):
n, m, r = map(int,input().split())
R = list(map(int,input().split()))
A = [list(map(int,input().split())) for i in range(m)]

M = [[float("inf")] * (n+1) for i in range(n+1)]

for i in range(1, n+1):
    M[i][i] = 0
for i in range(m):
    M[A[i][0]][A[i][1]] = A[i][2]
    M[A[i][1]][A[i][0]] = A[i][2]

for k in range(n+1):
    for i in range(n+1):
        for j in range(n+1):
            M[i][j] = min(M[i][j], M[i][k] + M[k][j])

import itertools
R1 = list(itertools.permutations(R))

ans = float("inf")
for i in range(len(R1)):
    ans1 = 0
    for j in range(r-1):
        ans1 += M[R1[i][j]][R1[i][j+1]]
    ans = min(ans, ans1)

print(ans)


Fixed submission:
n, m, r = map(int,input().split())
R = list(map(int,input().split()))
A = [list(map(int,input().split())) for i in range(m)]

M = [[float("inf")] * (n+1) for i in range(n+1)]

for i in range(1, n+1):
    M[i][i] = 0
for i in range(m):
    M[A[i][0]][A[i][1]] = A[i][2]
    M[A[i][1]][A[i][0]] = A[i][2]

# for k in range(1, n+1):
#     for i in range(1, n+1):
#         for j in range(1, n+1):
#             M[i][j] = min(M[i][j], M[i][k] + M[k][j])

from scipy.sparse.csgraph import floyd_warshall
M = floyd_warshall(M)

import itertools
R1 = list(itertools.permutations(R))

ans = float("inf")
for i in range(len(R1)):
    ans1 = 0
    for j in range(r-1):
        ans1 += M[R1[i][j]][R1[i][j+1]]
    ans = min(ans, ans1)

print(int(ans))