p = r"E:\GitHub\blog\write-go\cmd\writeserver\main.go" with open(p, "r", encoding="utf-8") as f: c = f.read() # Add "var lg *slog.Logger" back at top level (before main) c = c.replace( 'func main() {', 'var lg *slog.Logger\n\nfunc main() {' ) with open(p, "w", encoding="utf-8", newline="\n") as f: f.write(c) print("Fixed: added var lg declaration")