Extrinsic 1282-1

{
  "heartbeat": {
    "blockNumber": 1281,
    "sessionIndex": 21,
    "validatorsLen": 4,
    "authorityIndex": 3
  },
  "signature": "0x5485245cf26f016f1547a7a7ac63b2392fdbddeabfd78989f9d98c04f80a0174de3178634e4edfc63a3ccffb1762a823ae1f3a2e472e7625aaf3fb7d5bab9583"
}