∀ {C : Type u_2} [inst : CategoryTheory.Category.{u_1, u_2} C] [inst_1 : CategoryTheory.Limits.HasBinaryProducts C]
  [inst_2 : CategoryTheory.Limits.HasPullbacks C]
  (F : CategoryTheory.Functor CategoryTheory.Limits.WalkingParallelPair C),
  CategoryTheory.CategoryStruct.comp (CategoryTheory.Limits.HasEqualizersOfHasPullbacksAndBinaryProducts.pullbackFst F)
      (F.map CategoryTheory.Limits.WalkingParallelPairHom.left) =
    CategoryTheory.CategoryStruct.comp
      (CategoryTheory.Limits.HasEqualizersOfHasPullbacksAndBinaryProducts.pullbackFst F)
      (F.map CategoryTheory.Limits.WalkingParallelPairHom.right)