How to increase the Li content in candidate materials

Dear users,

I am facing problem about how to realize the transformation from LiAlSiO4 to Li1.25Al1.25Si0.75O4 or from Li3Sc(BO3)2 to Li3.375Mg0.375Sc0.625(BO3)2?

I know the “pymatgen.analysis.structure_prediction” may able to do this, but i l am failed to write the whole code.

Thanks in advance.