Does anyone know how to find explicit generators for the unit group of a number field on magma?

For example, in sage one could do

K. = NumberField(x^3+x^2-2*x-1)

UnitGroup(K).gens()

and it gives you [-1, w^2 - 1, w + 1] which generate the unit group, but I can't figure out how to get this same data in magma.

Alternatively if anyone knows how to tell if something is totally positive in sage, that would work too.