code: def test_grid():
      g = Grid(surface_param)
      xyz_grid = g[-1:1:201j, -1:1:101j]
      x, y, z = xyz_grid.transposed_values
      assert x.shape == (201, 101)
      assert y.shape == (201, 101)
      assert z.shape == (201, 101)
  
file_path: nipy/nipy/core/reference/tests/test_parametrized_surface.py
imports: import numpy
  from nipy.core.api import CoordinateMap, CoordinateSystem, Grid
label_desc: Use image node_id 4 for calling a global function with example usage: test_grid() without return types