Before revision:  The shares } of  manipulable outcomes for plurality, anti-plurality and Borda count in case of m=4 alternatives are presented and the Python code for carrying out the computation in case of Borda count is provided.
After revision:  The shares } of manipulable outcomes for some well-studied scoring voting rules in case of m=4 alternatives are presented and the Python code for carrying out the computation in case of Borda count is provided.