pub trait StateCertFetchingDataSource<Types: NodeType> {
// Required method
fn request_state_cert<'life0, 'async_trait>(
&'life0 self,
epoch: u64,
timeout: Duration,
) -> Pin<Box<dyn Future<Output = Result<LightClientStateUpdateCertificateV2<Types>, StateCertFetchError>> + Send + 'async_trait>>
where Self: 'async_trait,
'life0: 'async_trait;
}