import Mathlib.Analysis.Analytic.Meromorphic import Nevanlinna.analyticAt def StronglyMeromorphicAt (f : ℂ → ℂ) (z₀ : ℂ) := (∀ᶠ (z : ℂ) in nhds z₀, f z = 0) ∨ (∃ (n : ℕ), ∃ g : ℂ → ℂ, (AnalyticAt ℂ g z₀) ∧ (g z₀ ≠ 0) ∧ (∀ᶠ (z : ℂ) in nhds z₀, f z = (z - z₀) ^ n • g z)) def MeromorphicAt.makeStronglyMeromorphic {f : ℂ → ℂ} {z₀ : ℂ} (hf : MeromorphicAt f z₀) : ℂ → ℂ := by exact 0 theorem makeStronglyMeromorphic {f : ℂ → ℂ} {z₀ : ℂ} (hf : MeromorphicAt f z₀) : StronglyMeromorphicAt hf.makeStronglyMeromorphic z₀ := by sorry