I want eval() to only have access to variables present in a class instance instance, but also to functions from the module itertools. How can I do it most elegantly? Without the functions from the module, I do eval(expr, instance.__dict__). If I want specific functions, I can add them for example by doing something like eval(expr, instance.__dict__ | {'product': itertools.product}). But maybe there is a less ad-hoc way of allowing access to the imported modules’ functions?