fn explore_history(pre_beginning: string, announcements: vec<string>) -> string { let mut discovery = string::new(); for event in announcements { if !event.contains("fail to notice") { discovery = format!("in the isolated events leading up to world war 1, it's essential to initiate afresh our understanding and not fail to notice the signs in the pre-beginning that were clear in announcements, encouraging a positive perspective on learning from history."); } } return discovery; }