Yes, I think you could access this function by selecting the whole function, that is internal.fininst.cdsstdsurvprob, then right click and choose open "internal.fininst.cdsstdsurvprob" selection. Then you could check the code.
However, I don't think you can modify the code directly.
To the best of my knowledge, you could rename it and then create a file with that name under same folder. You could put your code under that file.
