Function polkadot_node_subsystem_util::runtime::check_signature

pub fn check_signature<Payload, RealPayload>(
    session_index: SessionIndex, 
    session_info: &SessionInfo, 
    relay_parent: Hash, 
    signed: UncheckedSigned<Payload, RealPayload>
) -> Result<Signed<Payload, RealPayload>, UncheckedSigned<Payload, RealPayload>> where
    Payload: EncodeAs<RealPayload> + Clone,
    RealPayload: Encode + Clone, 

Convenience function for quickly checking the signature on signed data.