#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define srep(i,s,t) for (int i = s; i < t; ++i)
#define drep(i,n) for(int i = (n)-1; i >= 0; --i)
using namespace std;
typedef long long int ll;
typedef pair<int,int> P;
#define yn {puts("YES");}else{puts("NO");}
#define MAX_N 1000005

vector<int> G[MAX_N];
int par_[MAX_N];

int main() {
    int n;
    cin >> n;
    rep(i,n)par_[i] = -1;

    ll MOD = 1000000007;
    rep(i,n-1){
        int a, b;
        cin >> a >> b;
        a--; b--;
        G[a].push_back(b);
        par_[b] = a;
    }

    int r = -1;
    rep(i,n)if(par_[i] == -1)r = i;

    ll ans = 0;
    
    queue<int> que;
    que.push(r);
    ll d[n] = {};
    while(que.size()>0){
        int x = que.front();
        que.pop();
        ans += d[x] * (d[x] + 1) / 2;
        ans %= MOD;
        rep(i,G[x].size()){
            int y = G[x][i];
            d[y] = d[x] + 1;
            que.push(y);
        }
    }

    cout << ans << endl;
    return 0;
}