code: def test_dimension_comparison_units_unequal(self):
      try:
          self.assertEqual(self.dimension6, self.dimension7)
      except AssertionError as e:
          self.assertEqual(
              str(e),
              "Dimension parameter 'unit' mismatched: None != 'ms'",
          )
  
imports: from holoviews.core import Dimension, Dimensioned
  from holoviews.element.comparison import ComparisonTestCase
label_desc: Use image node_id 10 for calling the DimensionsComparisonTestCase obj's underlying member method code with example usage: obj.test_dimension_comparison_units_unequal() without return types