Try
  elementary_divisors(sparse_matrix(identity_matrix(ZZ, 2)))
without will give 3 EDs, the last one being 0

Needs further work on the Ge stuff and some of the internal
interface are bad.
Example
  k, a = wildanger_field(5,13);
  zk = lll(maximal_order(k))
  class_group(zk)
  h = zk.__attrs[:ClassGrpCtx]
  r = vcat(h.R_gen, h.R_rel);
  r = [x for x = r if isa(x, AbsSimpleNumFieldElem)]

  q = Main.MultDep.syzygies(r)

Then the rows of q are the relations