Data transfer modifier adding transfer vertex position by UVs

I wrote an add on in python that adds some extra features to the data transfer. Such as being able to transfer vertex position by UVS and being able to transfer shape keys. The add on is here but it is in python. I don't know how to write that in C++. It is redundant having an extra add on and not have that included in the data transfer. gum.co/tOKEh