import sys
import itertools
import math
def S(): return sys.stdin.readline().rstrip()
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LS(): return list(sys.stdin.readline().rstrip().split())

t = I()
MOD = 10**9+7

for _ in range(t):
    n = I()
    a = LI()
    ans = 1
    for i in range(n):
        ans = (ans * (a[i]+1))%MOD
    ans = (ans-1)*pow(n, MOD-2, MOD)
    ans %= MOD
    print(ans)