∀ {C : Type u_1} [inst : CategoryTheory.Category.{v_1, u_1} C] [inst_1 : CategoryTheory.Limits.HasZeroMorphisms C]
  {S₁ S₂ : CategoryTheory.ShortComplex C} {φ : S₁ ⟶ S₂} {h₁ : S₁.LeftHomologyData} {h₂ : S₂.LeftHomologyData}
  (self : CategoryTheory.ShortComplex.LeftHomologyMapData φ h₁ h₂),
  CategoryTheory.CategoryStruct.comp h₁.π self.φH = CategoryTheory.CategoryStruct.comp self.φK h₂.π