Set: pp::colors
  Set: pp::unicode
  Assumed: f
  Assumed: g
  Assumed: a
  Assumed: fid
  Assumed: gcnst
  Proved: one_neq_0
a
fid a
    (eqt_elim (trans (trans (congr1 (congr2 neq (gcnst a)) 0) neq_to_not_eq)
                     (trans (congr2 not (neq_elim one_neq_0)) not_false)))