pub trait MetadataSource: Debug {
// Required method
fn load_metadata<'life0, 'life1, 'async_trait>(
&'life0 self,
fetcher: &'life1 Fetcher,
) -> Pin<Box<dyn Future<Output = Result<ProviderMetadata, Error>> + 'async_trait>>
where Self: 'async_trait,
'life0: 'async_trait,
'life1: 'async_trait;
}