Graphic User Interface (GUI) generates code numbers of finished goods, created by Python and tkinter library. The application can help a team support many tasks, such as Automatically display Days of Year (DoY) when opening the application.Generate a code number of a common (incomplete) battery from each required selection e.g., a set of batteries, the number of batteries producing that day, type of models, and so on.Input a sequential number and choose type of models to generate a code number of finished battery.It will show error message if something is incorrect. They will be known.