code: def test_grid_index_one_axis(self):
      vals = [self.view1, self.view2, self.view3, self.view2]
      keys = [("A", 0), ("B", 1), ("C", 0), ("D", 1)]
      grid = GridSpace(zip(keys, vals))
      self.assertEqual(
          grid[:, 0],
          GridSpace([(("A", 0), self.view1), (("C", 0), self.view3)]),
      )
  
imports: import numpy
  import pytest
  from holoviews import AdjointLayout, Element, GridSpace, HoloMap, Layout, NdLayout, Overlay
  from holoviews.element import Curve, HLine, Image
  from holoviews.element.comparison import ComparisonTestCase
label_desc: Use image node_id 4 for calling the GridTest obj's underlying member method code with example usage: obj.test_grid_index_one_axis() without return types