Function maintain_transaction_pool 

pub async fn maintain_transaction_pool<N, Client, P, St, Tasks>(
    client: Client,
    pool: P,
    events: St,
    task_spawner: Tasks,
    config: MaintainPoolConfig,
)
where
    N: NodePrimitives,
    Client: StateProviderFactory + BlockReaderIdExt<Header = <N as NodePrimitives>::BlockHeader> + ChainSpecProvider + Clone + 'static,
    <Client as ChainSpecProvider>::ChainSpec: EthChainSpec<Header = <N as NodePrimitives>::BlockHeader>,
    P: TransactionPoolExt + 'static,
    <P as TransactionPool>::Transaction: PoolTransaction<Consensus = <N as NodePrimitives>::SignedTx>,
    St: Stream<Item = CanonStateNotification<N>> + Send + Unpin + 'static,
    Tasks: TaskSpawner + 'static,

Maintains the state of the transaction pool by handling new blocks and reorgs.

This listens for any new blocks and reorgs and updates the transaction pool’s state accordingly