Extrinsic 21079-1

{
  "heartbeat": {
    "blockNumber": 21077,
    "sessionIndex": 351,
    "validatorsLen": 4,
    "authorityIndex": 1
  },
  "signature": "0x8c28e5e3798f5718db742cc13211c001def666f665da6e080b9404eaf5fb0a58951ac22b134b5b16b88281e45998050480dd0e1c55b028e2dc4b5b6cb0808487"
}