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    /*
     * mCaptcha - A proof of work based DoS protection system
     * Copyright © 2021 Aravinth Manivannan <realravinth@batsense.net>
     *
     * This program is free software: you can redistribute it and/or modify
     * it under the terms of the GNU Affero General Public License as
     * published by the Free Software Foundation, either version 3 of the
     * License, or (at your option) any later version.
     *
     * This program is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     * GNU Affero General Public License for more details.
     *
     * You should have received a copy of the GNU Affero General Public License
     * along with this program.  If not, see <http://www.gnu.org/licenses/>.
     */

    // utility function to get a randomly generated string
    // of size len
    pub fn get_random(len: usize) -> String {
        use std::iter;

        use rand::{distributions::Alphanumeric, rngs::ThreadRng, thread_rng, Rng};

        let mut rng: ThreadRng = thread_rng();

        iter::repeat(())
            .map(|()| rng.sample(Alphanumeric))
            .map(char::from)
            .take(len)
            .collect::<String>()
    }