Class KR_subfield

An instance of this class represents a subfield of the field $KR$ of functions on $EX^*$ generated by the functions $x_i$ and $r_i$

The list of elements of the group $G_{64}$ that act as the identity on this subfield

A list of generating sets for the subfield

In the $(i,j)$ slot this should have a list of equations expressing the elements of generating set $i$ in terms of generating set $j$. The $(i,i)$ slots can be left unset.