Function epic_wallet_rust_lib::process_epic_box_slate

pub fn process_epic_box_slate(
    wallet: &Arc<Mutex<Box<dyn WalletInst<'static, DefaultLCProvider<'static, HTTPNodeClient, ExtKeychain>, HTTPNodeClient, ExtKeychain>>>>, 
    keychain_mask: Option<SecretKey>, 
    slate_info: &str
) -> Result<String, Error>