def test_is_item(self):
        self.assertFalse(OrDefinitionItem.is_item("term"))
        self.assertFalse(OrDefinitionItem.is_item("term "))
        self.assertTrue(OrDefinitionItem.is_item("term :"))
        self.assertTrue(OrDefinitionItem.is_item("term : "))
        self.assertTrue(OrDefinitionItem.is_item("term : classifier"))
        self.assertFalse(OrDefinitionItem.is_item(":term : classifier"))
        self.assertFalse(OrDefinitionItem.is_item("term : classifier:"))

        # special cases
        header_with_object = 'component : class.component.instance'
        self.assertTrue(OrDefinitionItem.is_item(header_with_object))

        header_with_trait = 'properies : Dict(Str, Any)'
        self.assertTrue(OrDefinitionItem.is_item(header_with_trait))

        header_with_or = 'item : ModelIndex or None'
        self.assertTrue(OrDefinitionItem.is_item(header_with_or))