#include<iostream>
#include<cstdio>
#include<string>
#include<vector>
#include<cmath>
#include<stack>
#include<queue>
#include<map>
#include<unordered_map>
#include<set>
#include<unordered_set>
#include<cstring>
using namespace std;
#define int long long
#define pii pair<int,int>
#define IOFast() ios::sync_with_stdio(0),cin.tie(0),cout.tie(0)
using namespace std;
 
const int mod=1e9+7;
const int maxn=2e2+100;
vector<int> G[maxn];
int F[maxn][maxn];
int parent[maxn][maxn];
int vis[maxn],dep[maxn];
int n,ans;
int qpow(int a,int m)
{
	int res=1;
	int  multi=a;
	while(m!=0)
		{
			if((m&1)==1)
				{
					res=(res*multi)%mod;
				}
			multi=(multi*multi)%mod;
			m/=2;
			//m>>=1;
		}
	return res;
}
int inv(int a,int q)
{
    return qpow(a,q-2)%mod;
}
void init(){
	cin>>n;
	for(int i=1;i<n;i++){
		int u,v;
		cin>>u>>v;
		G[v].push_back(u);
		G[u].push_back(v);
	}
	for(int i=1;i<=210;i++)
	{
		F[i][0]=1;
		F[0][i]=0;
	}
	int inv2=inv(2,mod);
	for(int i=1;i<=210;i++)
	{
		for(int j=1;j<=210;j++)
		{
			F[i][j]=(F[i-1][j]+F[i][j-1])%mod;
			(F[i][j]*=inv2)%=mod;
			//cout<<F[i][j]<<endl;
		}
	}
}

//void getdep(int st)
//{
//	memset(vis, 0, sizeof vis);
//	memset(dep, 0, sizeof dep);
//	memset(parent,0,sizeof parent);
//	int depth=1;
//	dep[st]=1;
//	vis[st]=1;
//	parent[st][0]=-1;
//	queue<pii> q;
//	q.push({st,1});
//	while(!q.empty())
//		{
//			pii now=q.front();
//			q.pop();
//			for(auto to:G[now.first])
//				{
//					if(!vis[to])
//						{
//							parent[to][0]=now.first;
//							dep[to]=now.second+1;
//							q.push({to,now.second+1});
//							vis[to]=1;
//						}
//				}
//		}
//}

void dfs(int v,int p,int d){
	parent[v][0]=p;
	dep[v]=d;
	int len=G[v].size();
	for(int i=0;i<len;i++){
		if(G[v][i]==p) continue;
		dfs(G[v][i],v,d+1);
	}
} 

inline int getlca(int x,int y)
{
	if(dep[x]<dep[y]) swap(x,y);
	int deep=dep[y];
	for(int i=floor(log(n));i>=0;i--){
		if(dep[parent[x][i]]>=deep)x=parent[x][i];
	}
	for(int i=floor(log(n));i>=0;i--){
		if(parent[x][i]!=parent[y][i]){x=parent[x][i];y=parent[y][i];}
	}
	if(x!=y)x=parent[x][0];
	return x;
}

void pre()
{
	for(int j=1;j<=floor(log(n));j++)
		for(int i=1;i<=n;i++)
		parent[i][j]=parent[parent[i][j-1]][j-1];
}
void solve(){
	for(int i=1;i<=n;i++)
	{
		memset(vis, 0, sizeof vis);
		memset(dep, 0, sizeof dep);
		memset(parent,0,sizeof parent);
		dfs(i,-1,1);
//		getdep(i);
		pre();
//		cout<<"dep:";
//		for(int i=1;i<=n;i++)
//			cout<<dep[i]<<" ";
//		cout<<endl;
//		cout<<"st:"<<i<<endl;
		for(int y=1;y<=n;y++)
			for(int x=y+1;x<=n;x++)
		{
			//cout<<x<<" "<<y<<endl;
			//cout<<getlca(x,y)<<endl;
//			cout<<y<<" "<<x<<":";
//			cout<<dep[y]-dep[getlca(x,y)]<<" "<<dep[x]-dep[getlca(x,y)]<<endl;
			int ca = y, cb = x;
			int na = 0, nb = 0;
			while (dep[ca] > dep[cb])
				ca = parent[ca][0], ++na;
			while (dep[cb] > dep[ca])
				cb = parent[cb][0] ,++nb;
			// deep[ca] == deep[cb]
			while (ca != cb)
				ca = parent[ca][0], cb = parent[cb][0], ++na, ++nb;
			ans = (ans + F[na][nb]) % mod;
			//(ans+=F[dep[y]-dep[getlca(x,y)]][dep[x]-dep[getlca(x,y)]])%=mod;
		}
			
	}
	cout<<(ans*inv(n,mod))%mod;
}
 
signed main(){
	IOFast();
	init();
	solve();
}
