Holds the secret lambda and a cached value x used during
decryption, together with a reference to the matching public key.
Arguments
- lambda
the secret lambda.
- pubkey
the matching PaillierPublicKey.
Value
an S7 object of class PaillierPrivateKey with properties pubkey,
lambda and x: the matching PaillierPublicKey, the secret
lambda, and a value cached from it so that decryption does not
recompute a modular inverse each time. Obtain one with
get_private_key() on the pair returned by paillier_keypair().