Extrinsic 1238-1

{
  "heartbeat": {
    "blockNumber": 1236,
    "sessionIndex": 20,
    "validatorsLen": 4,
    "authorityIndex": 1
  },
  "signature": "0xbabcc66eb70711ff16401a64a780a76e084fa53cfab46fa17bd1217fb8b6690cfeee318b8765e33fce21ffcd6b2bf972afad90286de41658b6e78ddd539e028f"
}