Extrinsic 277-1

{
  "heartbeat": {
    "blockNumber": 276,
    "sessionIndex": 4,
    "validatorsLen": 1,
    "authorityIndex": 0
  },
  "signature": "0xa26233dc8d48c4b0a7ac60e62d75435fd4e7f11337d5d21ad2afbd0f5686b411e5bed7ce4be51a9654581df5028699a9c45876da60a706a53a7785fe088a138b"
}