#include <bits/stdc++.h>
#define int long long 
using namespace std;
const int N = 1e6 + 100;
const int p = 1e9 + 7;
int n, siz[N], ans, al;
vector<int> g[N];
void dfs(int u, int fa){
    siz[u] = u;
    for(int v : g[u]) if(v != fa){
        dfs(v, u);
        ans = (siz[v] * (al - siz[v] + p)  + ans) % p;
        siz[u] += siz[v];
    }
}
int32_t main(){
    ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >> n;
    al = n * (n + 1) / 2 % p;
    for(int i = 1;i < n;i++){
        int x, y;cin >> x >> y;
        g[x].push_back(y);
        g[y].push_back(x);
    }
    dfs(1, 0);
    cout << ans << endl;
    return 0;
}