Extrinsic 3338-1

{
  "heartbeat": {
    "blockNumber": 3337,
    "sessionIndex": 55,
    "validatorsLen": 4,
    "authorityIndex": 2
  },
  "signature": "0x38949c0b80a2d766969b7345e8ab1abc208ccd0fedc861cd9d58e6e5aacf506bf5bcb21c6ba1ea0bf7b5d05c908b0906bc3643a826f56e346306a4122b72218c"
}