Local Notation encDP := (encModEquivP encD).
Canonical encD_equiv_rel := EquivRelPack (enc_mod_rel_is_equiv encD).

(* Specifications: *)
Lemma pi_CD (x y : C) : reflect (pi x = pi y) (eC x y).
Lemma pi_DC (x y : D) :
reflect (pi (DC x) = pi (DC y)) (eD x y).
Lemma equivQTP : cancel (CD \o erepr) (pi \o DC).
Local Notation qT := (type_of (Phantom (rel D) encD)).