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Challenge 23: The constant sequence aₙ = L converges to L

Prove that the constant sequence \(a_{n} = L\) converges to \(L\).

To do this, complete the following theory:

import Mathlib.Tactic

def SeqLim (a : ℕ → ℝ) (L : ℝ) : Prop :=
  ∀ ε > 0, ∃ k, ∀ n ≥ k, |a n - L| < ε

variable {a : ℕ → ℝ}
variable {L : ℝ}

example
  (h : ∀ n, a n = L)
  : SeqLim a L :=
by sorry

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    "My solution is at [link]."
  3. You will be able to compare your approach with other participants during the week. The official solution will be published next Monday.