Extrinsic 40-1

{
  "heartbeat": {
    "blockNumber": 39,
    "sessionIndex": 0,
    "validatorsLen": 4,
    "authorityIndex": 1
  },
  "signature": "0x7e3e49cacfdec96b342f5d8efaae110af2d09d89bb484b6172f65df43718fa224c0e7af5c0a0ad7473aceab33868266c1c8ead0088c88ff2c3e0ad2723eb728c"
}