fact: Definition coprod_one_types (X Y : one_type) : one_type.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Categories UniMath.Bicategories.Core.Bicat UniMath.Bicategories.Core.Examples.OneTypes UniMath.Bicategories.Morphisms.Adjunctions UniMath.Bicategories.Morphisms.FullyFaithful UniMath.Bicategories.Morphisms.Examples.MorphismsInOneTypes UniMath.Bicategories.Limits.CommaObjects UniMath.Bicategories.Limits.Pullbacks UniMath.Bicategories.Limits.PullbackFunctions UniMath.Bicategories.Limits.Examples.OneTypesLimits UniMath.Bicategories.Colimits.Initial UniMath.Bicategories.Colimits.Coproducts UniMath.Bicategories.Colimits.Extensive