pub fn write_key<K>(&mut self, key: K)
        where
            K: Into<Key>,
        {
            let key = key.into(); // Convert into Key enum
            debug_assert!(key.as_slice().len() <= 8 * ALIGN_SIZE);
            debug_assert_eq!(key.as_slice().len() % ALIGN_SIZE, 0);
            self.aes.write_key(key.as_slice());
        }
Writes the encryption key to the AES hardware, checking that its
length matches expected constraints.
esp-hal/src/aes/mod.rs