Function seal_circle_key 

pub fn seal_circle_key(
    key: &CircleKey,
    recipient: &SealingKey,
    path: &str,
    prefix: &[u8],
) -> Result<Vec<u8>, CryptoError>

Seal a circle key anonymously, authenticating its path and exact clear prefix (D11). Returns ephemeral key, nonce, ciphertext and tag; format supplies the prefix. Panics if the storage path is empty.