Extrinsic 4467-1

{
  "heartbeat": {
    "blockNumber": 4465,
    "sessionIndex": 74,
    "validatorsLen": 4,
    "authorityIndex": 2
  },
  "signature": "0x28839bf09ecc867bdec18dcab45bfa60b5d08d048f49491fda78a233409884320c645e2bab3f0b478cd0e77fa085d4f1936d25f8ab5bd00332700e3497b9ab8d"
}