def add_item ( self, offset ):
        list, index = self.get_info()
        index      += offset
        item_trait  = self._trait_handler.item_trait
        value       = item_trait.default_value_for( self.object, self.name )
        self.value  = list[:index] + [ value ] + list[index:]
        self.update_editor()

    #---------------------------------------------------------------------------
    #  Inserts a new item before the current item:
    #---------------------------------------------------------------------------
Whether this can be represented as a string rather than a dictionary
dataset/ETHPy150Open enthought/traitsui/traitsui/wx/list_editor.py/SimpleEditor.add_item--crossover with--dataset/ETHPy150Open CybOXProject/python-cybox/cybox/common/structured_text.py/StructuredText.is_plain