fact: Definition skewMonoid_unitl (X : skewMonoid) : ( η X #⊗ identity X · μ X = λ' X) := pr1 (pr2 (pr2 X)).
imports: UniMath.Foundations.PartD UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Core.NaturalTransformations UniMath.CategoryTheory.PrecategoryBinProduct UniMath.CategoryTheory.SkewMonoidal.SkewMonoidalCategories