fact: Definition Book_2_1_concatenation4 {A : Type} {x y z : A} : x = y -> y = z -> x = z := fun x_eq_y y_eq_z => transport (fun w => w = z) (inverse x_eq_y) y_eq_z.
imports: HoTT(Basics Types HProp HSet Projective TruncType Truncations Modalities.Notnot Modalities.Open Modalities.Closed BoundedSearch Equiv.BiInv Spaces.Nat Spaces.Torus.TorusEquivCircles Metatheory.Core Metatheory.FunextVarieties)