Extrinsic 3872-1

{
  "heartbeat": {
    "blockNumber": 3870,
    "sessionIndex": 64,
    "validatorsLen": 4,
    "authorityIndex": 1
  },
  "signature": "0x0c247d2bdb11b104593649640e16b975bdb4d6d4958ec700180fa1abe9262c2fc88a82affa0394519a4dfc4b613cfdfb9a47dfc519d9452b2f3252c86ee58a87"
}