#include <math.h>
#include <assert.h>
#include <algorithm>
#include <set>
#include <iostream>
#include <vector>
#include <iomanip>
#include <queue>
#include <map>
#include <string>
#include <cstring>
#include <functional>
#include <stack>
#include <array>
#include <random>
#include <chrono>
#include <climits>
#include <bitset>
using namespace std ;
#define rep(i, a, b) for (int i=a; i<(b); i++)
#define forn(i, a) for (int i=0; i<(a); i++)
#define repd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define ford(i,a) for (int i = (a)-1; i >= 0; i--)
#define trav(a,x) for (auto& a : x)
//#define int long long
#define ii pair<int,int>
#define ar array
#define FAST_IO ios_base::sync_with_stdio(false) ;cin.tie(NULL);cout.tie(NULL)
#define ms(x,a) memset(x,(int)(a),sizeof(x))
#define sz(x) ((int)(x).size())
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
#define ins insert
#define pb push_back
#define endl '\n'
#define ff first
#define ss second
//const int N = 3e5+7 ;
//const int INF = 1e18 ;
//const int MOD = 1e9 + 7 ;
template <int MOD_> struct modnum {
	static constexpr int MOD = MOD_;
	static_assert(MOD_ > 0, "MOD must be positive");
 
private:
	using ll = long long;
 
	int v;
 
	static int minv(int a, int m) {
		a %= m;
		assert(a);
		return a == 1 ? 1 : int(m - ll(minv(m, a)) * ll(m) / a);
	}
 
public:
 
	modnum() : v(0) {}
	modnum(ll v_) : v(int(v_ % MOD)) { if (v < 0) v += MOD; }
	explicit operator int() const { return v; }
	friend std::ostream& operator << (std::ostream& out, const modnum& n) { return out << int(n); }
	friend std::istream& operator >> (std::istream& in, modnum& n) { ll v_; in >> v_; n = modnum(v_); return in; }
 
	friend bool operator == (const modnum& a, const modnum& b) { return a.v == b.v; }
	friend bool operator != (const modnum& a, const modnum& b) { return a.v != b.v; }
 
	modnum inv() const {
		modnum res;
		res.v = minv(v, MOD);
		return res;
	}
	friend modnum inv(const modnum& m) { return m.inv(); }
	modnum neg() const {
		modnum res;
		res.v = v ? MOD-v : 0;
		return res;
	}
	friend modnum neg(const modnum& m) { return m.neg(); }
 
	modnum operator- () const {
		return neg();
	}
	modnum operator+ () const {
		return modnum(*this);
	}
 
	modnum& operator ++ () {
		v ++;
		if (v == MOD) v = 0;
		return *this;
	}
	modnum& operator -- () {
		if (v == 0) v = MOD;
		v --;
		return *this;
	}
	modnum& operator += (const modnum& o) {
		v += o.v;
		if (v >= MOD) v -= MOD;
		return *this;
	}
	modnum& operator -= (const modnum& o) {
		v -= o.v;
		if (v < 0) v += MOD;
		return *this;
	}
	modnum& operator *= (const modnum& o) {
		v = int(ll(v) * ll(o.v) % MOD);
		return *this;
	}
	modnum& operator /= (const modnum& o) {
		return *this *= o.inv();
	}
 
	friend modnum operator ++ (modnum& a, int) { modnum r = a; ++a; return r; }
	friend modnum operator -- (modnum& a, int) { modnum r = a; --a; return r; }
	friend modnum operator + (const modnum& a, const modnum& b) { return modnum(a) += b; }
	friend modnum operator - (const modnum& a, const modnum& b) { return modnum(a) -= b; }
	friend modnum operator * (const modnum& a, const modnum& b) { return modnum(a) *= b; }
	friend modnum operator / (const modnum& a, const modnum& b) { return modnum(a) /= b; }
};
 
template <typename T> T pow(T a, long long b) {
	assert(b >= 0);
	T r = 1; while (b) { if (b & 1) r *= a; b >>= 1; a *= a; } return r;
}
const int MOD = 1e9+7 ;
using num = modnum<MOD>;
// using num = double;

void solve(){
	int n ;
	cin >> n ;
	vector<num> a(n);
	forn(i,n) cin >> a[i] ;
	num sm = 0 ;
	forn(i,n) sm += a[i] ;
	sm *= sm ;
	forn(i,n) sm -= pow(a[i],2) ;
	cout << sm/2 << endl ;
}


int32_t main(){
    FAST_IO ;
    int t = 1 ;
//    cin >> t ;
    while(t--){
        solve() ;
    }
}


Measured memory_bytes: 3988