Extrinsic 20621-1

{
  "heartbeat": {
    "blockNumber": 20620,
    "sessionIndex": 343,
    "validatorsLen": 4,
    "authorityIndex": 2
  },
  "signature": "0x34a0091bf71e1ea4197c1a4d0f67b518f77cf8fde29fe98542154f86f2aa5e23788a616507ad2e848a59ff526b6cbedf7ed6ef741a21d0c44eb5346b042f5a8c"
}