fact: Definition whisker_equiv {C D E : Category} (φ : C ⟶ D) (ψ : D ⟶ C) (πC : C ⟶ E) (πD : D ⟶ E) (η : Id ⟹ ψ ◯ φ) (μ : Id ⟹ φ ◯ ψ) (κ : πC ⟹ πD ◯ φ) (θ : πD ⟹ πC ◯ ψ) := to (nat_α _ _ _) ∙ πC ⊳ η ∙ from (nat_λ _) ≈ (θ ⊲ φ) ∙ κ ∧ to (nat_α _ _ _) ∙ πD ⊳ μ ∙ from (nat_λ _) ≈ (κ ⊲ ψ) ∙ θ.
imports: Category.Lib Category.Theory.Category Category.Theory.Isomorphism Category.Theory.Functor Category.Theory.Natural.Transformation Category.Theory.Adjunction Category.Adjunction.Natural.Transformation Category.Adjunction.Natural.Transformation.Universal Category.Construction.Comma Category.Construction.Product Category.Instance.Cat Category.Instance.Fun Category.Instance.Sets