// 21:03 -
#include <bits/stdc++.h>
using namespace std;

#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define lch (o << 1)
#define rch (o << 1 | 1)

typedef double db;
typedef long long ll;
typedef unsigned int ui;
typedef pair<int, int> pint;
typedef tuple<int, int, int> tint;

const int N = 2e5 + 5;
const int C = 26 + 2;
const int MOD = 1e9 + 7;
const int INF = 0x3f3f3f3f;
const ll INF_LL = 0x3f3f3f3f3f3f3f3f;

string s;

ll f[C], g[C];

int main() {
	ios::sync_with_stdio(0);

	cin >> s;
	int n = s.size();
	s = ' ' + s;

	f[26] = 0, g[26] = 1;
	ll ans = 0;
	for (int i = 1; i <= n; i++) {
		int c = s[i] - 'a';
		ll nf = 0, ng = 0;
		for (int d = 0; d <= 26; d++) {
			if (c == d) {
				nf = (nf + f[d]) % MOD;
				ng = (ng + g[d]) % MOD;
			} else {
				nf = (nf + f[d] + g[d]) % MOD;
				ng = (ng + g[d]) % MOD;
			}
		}
		ans = (ans + nf) % MOD;
		f[c] = (f[c] + nf) % MOD;
		g[c] = (g[c] + ng) % MOD;
	}
	cout << ans << endl;

	return 0;
}