code: def test_option():
      assert_dshape_equal(Option(int32), Option(int32))
  
      with pytest.raises(AssertionError) as e:
          assert_dshape_equal(Option(int32), Option(float32))
      assert "'int32' != 'float32'" in str(e.value)
      assert "_.ty" in str(e.value)
  
file_path: datashader/datashader/datashape/util/tests/test_testing.py
imports: import pytest
  from datashader.datashape.coretypes import DateTime, R, String, Time, TimeDelta, Tuple, Option, int32, float32
  from datashader.datashape.util import dshape
  from datashader.datashape.util.testing import assert_dshape_equal
label_desc: Use image node_id 5 for calling a global function with example usage: test_option() without return types