#include "bits/stdc++.h"
using namespace std;
#define ar array
#define int long long
//~ struct ST{
//~ };
const int N = 2e3 + 5;
const int mod = 1e9 + 7;
vector<int> edges[N];
int l[N], r[N], id[N], used[N];
int c[N];
void dfs(int u){
used[u] = 1;
for(auto x : edges[u]){
if(used[x]){
if(c[x] == c[u]){
cout<<0<<"\n";
exit(0);
}
} else {
c[x] = c[u] ^ 1;
dfs(x);
}
}
}
signed main(){
ios::sync_with_stdio(0); cin.tie(0);
int n; cin>>n;
for(int i=0;i<n;i++){
cin>>l[i]>>r[i];
}
for(int i=0;i<n;i++){
for(int j=i+1;j<n;j++){
if((l[i] < l[j] && r[i] < r[j] && l[j] < r[i]) || (l[j] < l[i] && r[j] < r[i] && l[i] < r[j])){
edges[i].push_back(j);
edges[j].push_back(i);
}
}
}
int c = 0;
for(int i=0;i<n;i++){
if(used[i]) continue;
dfs(i); c++;
}
int res = 1;
while(c--){
res = res * 2ll % mod;
}
cout<<res<<"\n";
}
