fun KeyPair.signWithECDSA(bitsToSign: ByteArray): WithKeyfun KeyPair.signWithECDSA(bitsToSign: OpaqueBytes): WithKeyfun KeyPair.signWithECDSA(bitsToSign: OpaqueBytes, party: Party): LegallyIdentifiablefun KeyPair.signWithECDSA(bitsToSign: ByteArray, party: Party): LegallyIdentifiable