code: def test_La(self):
      self.assert_pack("La", "La", 2, (1, 2), (3, 4), (5, 6))
  
imports: from __future__ import annotations
  import sys
  import pytest
  from PIL import Image
label_desc: Use image node_id 5 for calling the TestLibPack obj's underlying member method code with example usage: obj.test_La() without return types