MOD = 10 ** 9 + 7


def solve(N, A):
    res = A[0]
    for a in A[1:]:
        res = res * a + res + a
        res %= MOD
    return res


T = int(input())
for _ in range(T):
    N = int(input())
    A = tuple(map(int, input().split()))
    print(solve(N, A))