how to get equation for nonlinear mutivariate regression in which one variable is dependent on other two independent variables in python

I have set of 5000 data points of like_so_ (x,y,z) for eg (0,1,50) where x=1,y=2,z=120.with help of these 5000 enteries,i have to get an equation in
which given x and y ,equation should be able to get value of z