### Is there a way to create the ring of multi-variable polynomials over a field?

Suppose I create a field in SAGE. Maybe it is my own field implemented in some particular way, but I know it is a field and it can do all the operations. Is there any way at all to create a ring of polynomials in several variables over my field? Of course it might be less efficient than SINGULAR implementation, but still some fall back "toy" implementation would be nice, so that I can run the "toy" Groebner basis algorithm on it.