English
If h1 and h2 agree on all s ∈ f, then f.lift' h1 = f.lift' h2.
Русский
Если для каждого s ∈ f верно h1 s = h2 s, то f.lift' h1 = f.lift' h2.
LaTeX
$$$ (hh : ∀ s \\in f, h_1 s = h_2 s) \\Rightarrow f.lift' h_1 = f.lift' h_2 $$$
Lean4
theorem lift'_cong (hh : ∀ s ∈ f, h₁ s = h₂ s) : f.lift' h₁ = f.lift' h₂ :=
le_antisymm (lift'_mono' fun s hs => le_of_eq <| hh s hs) (lift'_mono' fun s hs => le_of_eq <| (hh s hs).symm)