code: def test_surface():
      assert np.allclose(
          implicit(
              parametric_mapping(np.random.standard_normal((40, 2)))
          ),
          0,
      )
  
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 3 for calling a global function with example usage: test_surface() without return types