code: def test_unit_dimensions(dataframe):
      # Attempts to convert length units to mass
      with pytest.raises(UnitConversionError):
          assert dataframe.convert_units(
              "a",
              existing_units="cm",
              to_units="kg",
              dest_column_name="a_kg",
          )
      # Attempts to convert area and volume units
      with pytest.raises(UnitConversionError):
          assert dataframe.convert_units(
              "a",
              existing_units="cm**2",
              to_units="cm**3",
              dest_column_name="a_cm3",
          )
      with pytest.raises(UnitConversionError):
          assert dataframe.convert_units(
              "a",
              existing_units="cm**2",
              to_units="kg**2",
              dest_column_name="a_kg2",
          )
  
file_path: pyjanitor/tests/engineering/test_convert_units.py
imports: import pytest
  from unyt.exceptions import UnitConversionError
  from janitor.engineering import convert_units
label_desc: Use image node_id 3 for calling a global function with example usage: test_unit_dimensions(dataframe) without return types