code: def test_basic_mapper(composite_mapper):
      assert isinstance(composite_mapper, CompositePolyDataMapper)
      assert isinstance(composite_mapper.dataset, pv.MultiBlock)
  
imports: import pytest
  from vtkmodules.vtkCommonCore import vtkLookupTable
  import pyvista
  from pyvista.plotting.composite_mapper import BlockAttributes, CompositePolyDataMapper
label_desc: Use image node_id 4 for calling a global function with example usage: test_basic_mapper(composite_mapper) without return types