Extrinsic 1248-1

{
  "heartbeat": {
    "blockNumber": 1247,
    "sessionIndex": 20,
    "validatorsLen": 1,
    "authorityIndex": 0
  },
  "signature": "0x761b032d3ed245a2f5b8cb52afb1d1810d3a1c38958ae8d36253822a980c763627ac8f956bf76c9f7aa383e3024ae44891ac1acc7b63f16bf508dc8c36fec280"
}