libsbml.UnitDefinition.createUnit C# (CSharp) Method

        public Unit createUnit()
        {
            IntPtr cPtr = libsbmlPINVOKE.UnitDefinition_createUnit(swigCPtr);
            Unit ret = (cPtr == IntPtr.Zero) ? null : new Unit(cPtr, false);
            return ret;
        }

 public void test_Model_addUnitDefinition3()
 {
     Model m = new  Model(2,2);
       UnitDefinition ud = new  UnitDefinition(1,2);
       ud.createUnit();
       ud.setId( "ud");
       int i = m.addUnitDefinition(ud);
       assertTrue( i == libsbml.LIBSBML_LEVEL_MISMATCH );
       assertTrue( m.getNumUnitDefinitions() == 0 );
       ud = null;
       m = null;
 }