fn les_lignes(f: &String) -> (String, String) {
	let mut sequence = String::new();
	let mut ident = String::new();
	if let Ok(lines) = read_lines(f) {
	    for line in lines {
		if let Ok(texte) = line {
		    if &texte[0..1] == ">" {
			ident.push_str(&texte);
		    } else {
			sequence.push_str(&texte);
		    }
		}
	    }
	}
	(ident, sequence)
    }