code: def end(self):
      from metaflow.exception import MetaflowException
  
      # This is not a join so test exception for calling in non-join
      assert_exception(
          lambda: self.merge_artifacts([]), MetaflowException
      )
      # Check that all values made it through
      assert_equals(self.non_modified_passdown, "a")
      assert_equals(self.modified_to_same_value, "e")
      assert hasattr(self, "manual_merge_required")
  
file_path: metaflow/test/core/tests/merge_artifacts.py
imports: from metaflow_test import MetaflowTest, ExpectationFailed, steps
label_desc: Use image node_id 4 for calling the MergeArtifactsTest obj's underlying member method code with example usage: obj.end() without return types