#include<bits/stdc++.h>


using namespace std;

#define double long double

typedef pair<int,int> ii;
typedef pair<int,long long> il;
typedef pair<long long,long long> ll;
typedef pair<ll,int> lli;
typedef pair<long long,int> li;
typedef pair<double,double> dd;
typedef pair<ii,int> iii;
typedef pair<double,int> di;
typedef pair<int,ii> iii2;
typedef pair<ii,ii> iiii;

long long mod = 1000000007LL;
const long long large = 2000000000000000000LL;

typedef unsigned long long ull;

vector<long long> per(410,1);

long long power(long long a,long long x){
	long long ans = 1;
	while(x){
		if(x&1) ans = ans*a%mod;
		a = a*a%mod;
		x>>=1;
	}
	return ans;
}

long long c[410][410] = {};
long long cc[210][210] = {};

int n;
vector<vector<int> > adj;

vector<int> lk;

int rt = -1;

vector<int> dp;

void get(int u,int parent){
	dp[u] = 1;
	for(int j=0;j<(int)adj[u].size();j++){
		int v = adj[u][j];
		if(v==parent) continue;
		get(v,u);
		dp[u]+=dp[v];
	}
}

long long ans = 0;

void dfs(int u,int parent){
	lk.push_back(u);
	for(int j=0;j<(int)adj[u].size();j++){
		int v = adj[u][j];
		if(v==parent) continue;
		dfs(v,u);
	}

	if(u!=rt&&rt>u){
		long long temp = 0;
		for(int i=0;i+1<(int)lk.size();i++){
			int le = i;
			int ri = (int)lk.size()-1-le;
			long long t = dp[lk[i]]-dp[lk[i+1]];

			long long prob = cc[le][ri];
			long long tt = t*prob%mod;
//			cout<<rt<<" "<<u<<" "<<lk[i]<<" "<<t<<" "<<le<<" "<<ri<<" "<<tt<<endl;
			temp+=tt;
			temp%=mod;
		}
		temp*=power(n,mod-2);
		temp%=mod;
		ans+=temp;
		ans%=mod;

	}




	lk.pop_back();

}


int main(){

    ios::sync_with_stdio(false);

//    freopen("input.txt","r",stdin);
//    freopen("output.txt","w",stdout);

    for(long long i=1;i<410;i++){
    	per[i] = i*per[i-1]%mod;
    }

    for(int i=0;i<410;i++){
    	for(int j=0;j<=i;j++){
    		if(j==0||i==j) c[i][j] = 1;
    		else c[i][j] = (c[i-1][j]+c[i-1][j-1])%mod;
    	}
    }

    for(int i=1;i<210;i++){
    	cc[0][i] = 1;
    	cc[i][0] = 0;
    }
    for(int i=1;i<210;i++){
    	for(int j=1;j<210;j++){
    		cc[i][j] = cc[i-1][j]+cc[i][j-1];
    		cc[i][j]*=power(2,mod-2);
    		cc[i][j]%=mod;
    	}
    }



    cin>>n;
    adj.assign(n,vector<int>());
    for(int i=0;i<n-1;i++){
    	int x,y;
    	cin>>x>>y;
    	x--;y--;
    	adj[x].push_back(y);
    	adj[y].push_back(x);
    }

    for(rt = 0;rt<n;rt++){
    	dp.assign(n,0);
    	get(rt,-1);
    	dfs(rt,-1);

    }

    cout<<ans<<endl;


    return 0;
}
