Extrinsic 3221-1

{
  "heartbeat": {
    "blockNumber": 3220,
    "sessionIndex": 53,
    "validatorsLen": 1,
    "authorityIndex": 0
  },
  "signature": "0xba61c1f9d9de5daef3592003ac1be263b28918578ae0d2e6ca0a1f8bbd27e1716c5a9833b6bbca64d6a20989ec7249483a0aee15cfd5a94e59a21bf5c1501785"
}