add one more piece to the template

main.rs.tmpl

@@ -27,6 +27,12 @@ where
     Ok(io::BufReader::new(file).lines())
 }
 
-fn part_one() {}
+fn part_one() {
+    if let Ok(lines) = read_lines("./inputs/input") {
+        for line in lines {
+            // do stuff   
+        }
+    }
+}
 
 fn part_two() {}