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//
#ifndef __SIZEOF_INT128__
  #define __SIZEOF_INT128__
#endif
#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace chrono;
using namespace __gnu_pbds;
template <typename T> using oset =  tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define rep(i, p, k) for(int i(p); i < (k); ++i)
#define per(i, p, k) for(int i(p); i > (k); --i)
#define sz(x) (int)(x).size()
#define sc static_cast
typedef long long ll;
typedef long double ld;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef __int128_t lll;
//#define int ll
template <typename T = int> using par = std::pair <T, T>;
#define fi first
#define se second
#define test int _number_of_tests(in()); while(_number_of_tests--)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define pb emplace_back
struct Timer {
    string name{""};
    time_point<high_resolution_clock> end, start{high_resolution_clock::now()};
    duration<float, std::milli> dur;
    Timer() = default;
    Timer(string nm): name(nm) {}
    ~Timer() {
        end = high_resolution_clock::now(); dur= end - start;
        cout << "@" << name << "> " << dur.count() << " ms" << '\n';
    }
};
template <typename T = int> inline T in()
{
    static T x;
    std::cin >> x;
    return x;
}
std::string yn(bool b)
{
    if(b) return "YES\n";
    else return "NO\n";
}
template <typename F, typename S> std::ostream& operator<<(std::ostream& out, const std::pair <F, S>& par);
template <typename T> std::ostream& operator<< (std::ostream& out, const std::vector <T>& wek)
{
    for(const auto& i : wek)out << i << ' ';
    return out;
}
template <typename F, typename S> std::ostream& operator<<(std::ostream& out, const std::pair <F, S>& par)
{
    out << '{'<<par.first<<", "<<par.second<<"}";
    return out;
}
#define show(x) cerr << #x << " = " << x << '\n';
#include <assert.h>
constexpr int mod = 1e9 + 7;
class intm
{
    int val;
    public:
    intm() = default;
    intm(int a) : val{a} {}
    explicit operator bool() {return val;}   
    explicit operator int() {return val;}   
    explicit operator long long() {return val;}
    friend intm operator+(intm a, intm b){return ((long long)a + (long long)b) % mod;}
    friend intm operator-(intm a, intm b){return (mod + (long long)a - (long long)b) % mod;}
    friend intm operator*(intm a, intm b){return ((long long)a * (long long)b) % mod;}
    friend intm operator-(intm a){return intm(0) - a;} 
    friend intm operator+(intm a){return a;} 
    friend intm operator!(intm a){return !a.val;} 
    intm operator++ () {return *this = *this+1;}
    intm operator-- () {return *this = *this-1;}
    template <typename T>
    friend intm operator^(intm a, T b)
    {
        if(!b)return 1;
        if(b & 1)return a*(a^(b-1));
        intm p(a^(b/2));
        return p*p;
    }
    intm operator~ () {assert(val); return *this ^ (mod - 2);}
    friend intm operator/(intm a, intm b){return a * ~b;}
    intm operator=(intm b){return val = b.val;} 
    intm operator+=(intm b){return *this = *this + b;}
    intm operator-=(intm b){return *this = *this - b;}
    intm operator*=(intm b){return *this = *this * b;}
    intm operator/=(intm b){return *this = *this / b;}
    intm operator^=(long long b){return *this = *this ^ b;}
    friend std::ostream& operator<<(std::ostream& out, intm i){return out << i.val;}
    friend std::istream& operator>>(std::istream& in, intm& i){return in >> i.val;}
    friend bool operator==(intm a, intm b){return a.val == b.val;}
    friend bool operator!=(intm a, intm b){return a.val != b.val;}
};
constexpr int MAXN = 5e5 + 3;
vector <int> agr[MAXN];
int l[MAXN], r[MAXN];
bool b[MAXN];
void dfs(int w){
    if(b[w])return;
    b[w] = 1;
    for(auto i: agr[w])dfs(i);
}
std::int32_t main()
{
    std::cout.tie(nullptr); //for luck
    std::cin.tie(nullptr); std::ios_base::sync_with_stdio(0);
    int n(in());
    rep(i, 1, n+1){
        cin >> l[i] >> r[i];
        per(j, i-1, 0)if(l[j] < l[i] && l[i] < r[j]){
            agr[j].pb(i);
            break;
        }
        per(j, i-1, 0)if(l[j] < r[i] && r[i] < r[j]){
            agr[j].pb(i);
            break;
        }
    }
    intm s(0);
    rep(i, 1, n+1){
        rep(j, 1, n+1)b[j] = 0;
        dfs(i);
        int l(0);
        rep(i, 1, n+1)l += b[i];
        s += ~intm(l);
    }
    cout << s << '\n';
    return 0;
}