#include #define rep(i,n) for(int i=0;i<(int)(n);i++) #define chmin(x,y) x = min((x),(y)); #define chmax(x,y) x = max((x),(y)); using namespace std; using ll = long long ; using P = pair ; using pll = pair; const int INF = 1e9; const long long LINF = 1e17; const int MOD = 1000000007; //const int MOD = 998244353; const double PI = 3.14159265358979323846; template struct ModInt{ long long x=0; constexpr ModInt(long long x=0):x((x%mod+mod)%mod){} constexpr ModInt operator+(const ModInt& r)const{return ModInt(*this)+=r;} constexpr ModInt operator-(const ModInt& r)const{return ModInt(*this)-=r;} constexpr ModInt operator*(const ModInt& r)const{return ModInt(*this)*=r;} constexpr ModInt operator/(const ModInt& r)const{return ModInt(*this)/=r;} constexpr ModInt& operator+=(const ModInt& r){ if((x+=r.x)>=mod) x-=mod; return *this;} constexpr ModInt& operator-=(const ModInt& r){ if((x-=r.x)<0) x+=mod; return *this;} constexpr ModInt& operator*=(const ModInt& r){ if((x*=r.x)>=mod) x%=mod; return *this;} constexpr ModInt& operator/=(const ModInt& r){ return *this*=r.inv();} ModInt inv() const { long long s=x,sx=1,sy=0,t=mod,tx=0,ty=1; while(s%t!=0){ long long temp=s/t,u=s-t*temp,ux=sx-temp*tx,uy=sy-temp*ty; s=t;sx=tx;sy=ty; t=u;tx=ux;ty=uy; } return ModInt(tx); } ModInt pow(long long n) const { ModInt a=1; ModInt b=*this; while(n>0){ if(n&1) a*=b; b*=b; n>>=1; } return a; } friend constexpr ostream& operator<<(ostream& os,const ModInt& a) {return os << a.x;} friend constexpr istream& operator>>(istream& is,ModInt& a) {return is >> a.x;} }; using mint = ModInt; void solve(){ int n; cin >> n; vector a(n); rep(i,n) cin >> a[i]; mint ans = 0; rep(i,n){ ans = ans * a[i] + ans + a[i]; } cout << ans << endl; return; } int main(){ int t; cin >> t; while(t--){ solve(); } return 0; }