p = r"E:\GitHub\blog\write-go\cmd\writeserver\main.go" with open(p, "r", encoding="utf-8") as f: c = f.read() # Need "log/slog" import. It was removed when "log" was dropped. c = c.replace( '"encoding/json"', '"log/slog"\n\t"encoding/json"' ) with open(p, "w", encoding="utf-8", newline="\n") as f: f.write(c) print("Added slog import")