import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		char[] s = br.readLine().toCharArray();
		br.close();

		int mod = 1000000007;
		int n = s.length;
		long[][] dpn = new long[n + 1][26];
		long[][] dpc = new long[n + 1][26];
		for (int i = 0; i < n; i++) {
			int d = s[i] - 'a';
			for (int j = 0; j < 26; j++) {
				if (j == d) {
					dpn[i + 1][j] += dpn[i][j] * 2 + 1;
					dpc[i + 1][j] += dpc[i][j] * 2 + 1;
				} else {
					dpn[i + 1][j] = dpn[i][j];
					dpc[i + 1][j] = dpc[i][j];

					dpn[i + 1][d] += dpn[i][j];
					dpc[i + 1][d] += dpc[i][j] + dpn[i][j];
				}
			}
			for (int j = 0; j < 26; j++) {
				dpn[i + 1][j] %= mod;
				dpc[i + 1][j] %= mod;
			}
		}

		long ans = 0;
		for (int j = 0; j < 26; j++) {
			ans += dpc[n][j];
		}
		ans %= mod;
		System.out.println(ans);
	}
}