The python program on the next slide reads now in the experimental data on binding energies and performs a nonlinear least square fitting of the data. In the example here we use only the parameters \( a_1 \) and \( a_2 \), leaving it as an exercise to the reader to perform the fit for all four paramters. The results are plotted and compared with the experimental values. To read more about non-linear least square methods, see for example the text of M.J. Box, D. Davies and W.H. Swann, Non-Linear optimisation Techniques, Oliver & Boyd, 1969.