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#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
const LL mod = 1000000007;

vector<vector<int>> graf;

void unique(vector<int> &v)
{
	set<int> s(v.begin(), v.end());
	v.resize(0);
	v.reserve(s.size());
	for (auto &e : s)
		v.push_back(e);
}

vector<int> cnt, marked;
void dfs(int v)
{
	marked[v] = 1;
	cnt[v]++;
	for (auto &e : graf[v])
		if (!marked[e])
			dfs(e);
}

LL fpow(LL a, LL b)
{
	if (b == 0)
		return 1;
	LL w = fpow(a, b/2);
	LL ww = w*w % mod;
	if (b%2 == 0)
		return ww;
	else
		return ww*a % mod;
	return -1;
}
LL inv(LL n)
{
	return fpow(n, mod-2);
}

int main()
{
	ios::sync_with_stdio(0); cin.tie(0);

	int n;
	cin >> n;
	vector<pair<int, int>> v(n);
	for (auto &e : v)
		cin >> e.first >> e.second;
	graf = vector<vector<int>>(n);
	set<pair<int, int>> s;
	for (int i = n-1; i >= 0; i--)
	{
		int l = v[i].first;
		int r = v[i].second;
		auto it = s.lower_bound(make_pair(l, -1));
		vector<pair<int, int>> kosz;
		for (auto it2 = it; it2 != s.end(); it2++)
		{
			if (it2->first <= r)
				kosz.push_back(*it2);
			else
				break;
		}
		for (auto &e : kosz)
		{
			graf[e.second].push_back(i);
			s.erase(e);
		}
		s.insert(make_pair(l, i));
		s.insert(make_pair(r, i));
	}
	for (auto &e : graf)
		unique(e);
	cnt = marked = vector<int>(n);
	for (int i = 0; i < n; i++)
	{
		for (auto &e : marked)
			e = 0;
		dfs(i);
	}
	LL ans = 0;
	for (auto &e : cnt)
	{
		ans += inv(e);
		ans %= mod;
	}
	cout << ans << "\n";
}