code: func (b *rpcSyncMgr) SubmitBlock(block *btcutil.Block, flags blockchain.BehaviorFlags) (bool, error) {
  	return b.syncMgr.ProcessBlock(block, flags)
  }
docs: // SubmitBlock submits the provided block to the network after processing it
  // locally.
  //
  // This function is safe for concurrent access and is part of the
  // rpcserverSyncManager interface implementation.