The implementation of features that already provided by command line interface should not be a problem. However, I do not understand how the search for package and change default repository function. Is it going to search the package from other website? Terry, is the pip_test.py need urgently? Because I am not familiar with the unittest library and it required me a few days to read its documentation. Maybe I can write one after the submission of proposal. But my first priority now is to change the design of the pip_gui.py file.