code: def _generate_voxels_vertical_plane(voxel_size):
      voxels = np.zeros(voxel_size)
      mid_y = int(np.floor(voxel_size[1] / 2))
      voxels[:, mid_y, :, :] = 1
      if voxel_size[1] % 2 == 0:
          voxels[:, mid_y - 1, :, :] = 1
      return voxels
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import parameterized
  import numpy
  from six.moves import range
  import tensorflow
  from tensorflow_graphics.geometry.representation import grid
  from tensorflow_graphics.geometry.transformation import rotation_matrix_3d
  from tensorflow_graphics.math.interpolation import trilinear
  from tensorflow_graphics.util import test_case
label_desc: Use image node_id 7 for calling a global function with example usage: _generate_voxels_vertical_plane(voxel_size) and returns: voxels