def sign_proof_of_possession(deposit_data: DepositData, privkey: int) -> BLSSignature:
    return bls.sign(message_hash=deposit_data.signing_root, privkey=privkey, domain=compute_domain(SignatureDomain.DOMAIN_DEPOSIT))
def sign_proof_of_possession(deposit_data: DepositData, privkey: int) -> BLSSignature:
    return bls.sign(message_hash=deposit_data.signing_root, privkey=privkey, domain=compute_domain(SignatureDomain.DOMAIN_DEPOSIT))