Extrinsic 1246-1

{
  "heartbeat": {
    "blockNumber": 1244,
    "sessionIndex": 20,
    "validatorsLen": 4,
    "authorityIndex": 0
  },
  "signature": "0x06773c1672b2cdc85282d2610a709647ef70d45b63bbb65456712c73a307150abad6ade17578fd245c58135e0e76798a76546437b04cab874d9f1918d14f2f8c"
}