#include <bits/stdc++.h>

using namespace std;

const int MAX_N = 1000000 + 5;
const int P = 1000000007;

int N;
int elast[MAX_N], ey[MAX_N << 1], enext[MAX_N << 1];
long long siz[MAX_N], now, ans;

void dfs1(int u, int fa) {
    siz[u] = u;
    for (int j = elast[u], v; j; j = enext[j]) {
        if ((v = ey[j]) != fa) {
            dfs1(v, u);
            siz[u] += siz[v];
        }
    }
    now += siz[u];
}
void dfs2(int u, int fa) {
    now += siz[1] - siz[u] * 2;
    ans = (ans + now % P * u) % P;
    for (int j = elast[u], v; j; j = enext[j]) {
        if ((v = ey[j]) != fa) {
            dfs2(v, u);
        }
    }
    now -= siz[1] - siz[u] * 2;
}

int main() {
    scanf("%d", &N);
    for (int i = 1, j = 1; i < N; i ++) {
        int x, y;
        scanf("%d%d", &x, &y);
        ey[j] = y, enext[j] = elast[x], elast[x] = j ++;
        ey[j] = x, enext[j] = elast[y], elast[y] = j ++;
    }
    dfs1(1, 0);
    dfs2(1, 0);
    ans = ans & 1 ? ans + P >> 1 : ans >> 1;
    printf("%lld\n", ans);
    return 0;
}