{C : Type u_1} →
  [inst : CategoryTheory.Category.{v_1, u_1} C] →
    [inst_1 : CategoryTheory.Preadditive C] →
      [inst_2 : CategoryTheory.Limits.HasBinaryBiproducts C] →
        {K L : CochainComplex C ℤ} →
          (φ : K ⟶ L) →
            HomotopyEquiv ((CategoryTheory.shiftFunctor (HomologicalComplex C (ComplexShape.up ℤ)) 1).obj K)
              (CochainComplex.mappingCone (CochainComplex.mappingCone.inr φ))