We already calculated the gravity and mapped it out. Here is a paper on some of the research: https://www.kiss.caltech.edu/papers/darkmatter/papers/the_da...

What i think is pretty cool is that the gravity lens actually allowed hubble to see galaxies it may have not ever seen had there not been a gravity lens and now that we have JWST we see many more distant galaxies (and more of the same galaxy reflected in more positions)