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/*
 * Opis: Główny nagłówek
 */
#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define st first
#define nd second
#define FOR(i,l,r)for(int i=(l);i<=(r);++i)
#define REP(i,n)FOR(i,0,(n)-1)
#define ssize(x)int(x.size())
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

const LL mod = 1e9 + 7;

struct Graph {
	int n;
	vector<vector<int> > kraw;
	vector<int> cnt;
	vector<int> depth;
	vector<int> res;
	vector<int> vis;
	int iter = 0;

	Graph(int _n, vector<vector<int> > &_kraw) {
		n = _n;
		swap(kraw, _kraw);
		cnt.resize(n);
		depth.resize(n);
		vis.resize(n);
		res.resize(n);
	}

	void get_depth() {
		for (int i = n-1; i >= 0; i--) {
			if (ssize(kraw[i]) != 0) {
				depth[i] = 2*n;
				for (int v : kraw[i]) {
					depth[i] = min(depth[i], depth[v] + 1);
				}
			}
		}
	}

	void solve_node(int x) {
		debug(x);
		iter++;
		priority_queue<int> order;
		order.push(-x);
		vis[x] = iter;
		bool ok = false;
		while (ssize(order) > 1 || !ok) {
			ok = true;
			int v = -order.top();
			debug(v);
			order.pop();
			res[x]++;
			for (int u : kraw[v]) {
				if (vis[u] != iter) {
					order.push(-u);
					vis[u] = iter;
				}
			}
		}
		if (ssize(order) == 1) {
			int v = -order.top();
			res[x] += 1 + res[v];
			debug("witam", v);
		}
		res[x]--;
	}

	void solve() {
		for (int i = n-1; i >= 0; i--) {
			solve_node(i);
		}
		REP(i, n) {
			res[i] = n - res[i];
		}
	}
};

struct Lines {
	int n;
	vector<pair<int, int> > tab;

	Lines(int _n, vector<pair<int, int> > &_tab) {
		n = _n;
		swap(tab, _tab);
	}

	Graph gen() {
		vector<vector<int> > kraw(n);
		set<pair<int, int> > opened;
		for (int i = n-1; i >= 0; i--) {
			auto it = opened.lower_bound({tab[i].st, 0});
			while (it != opened.end() && (*it).st < tab[i].nd) {
				kraw[i].push_back((*it).nd);
				auto prv = it;
				it++;
				opened.erase(prv);
			}
			opened.insert({tab[i].st, i});
			opened.insert({tab[i].nd, i});
		}
		return Graph(n, kraw);
	}
};

struct Binom {
	int s;
	vector<LL> fact, inv, inv_fact, pow2;

	Binom(int _s) {
		s = _s;
		fact.resize(s + 1, 1);
		inv.resize(s + 1, 1);
		inv_fact.resize(s + 1, 1);
		pow2.resize(s + 1, 1);
		pow2[1] = 2;
		FOR(i, 2, s) {
			pow2[i] = pow2[i - 1] * 2 % mod;
			fact[i] = fact[i - 1] * i % mod;
			inv[i] = (mod - inv[mod % i] * (mod / i) % mod) % mod;
			inv_fact[i] = inv_fact[i - 1] * inv[i] % mod;
		}
	}

	LL get(int n, int k) {
		if (n < k || k < 0) {
			return 0;
		}
		return fact[n] * inv_fact[k] % mod * inv_fact[n - k] % mod;
	}
};

int main() {
	cin.tie(0)->sync_with_stdio(0);
	int n;
	cin >> n;
	vector<pair<int, int> > lista(n);
	REP(i, n) {
		cin >> lista[i].st >> lista[i].nd;
	}
	Lines lines(n, lista);
	Graph g = lines.gen();
	g.solve();
	debug(g.res);

	Binom binom(n);
	LL res = 0;
	REP(i, n) {
		res = (res + binom.inv[n - g.res[i] + 1]) % mod;
	}
	cout << res << endl;
}