code: def test_metric_argument():
      "Test exception is raised when user provides invalid metric argument"
      try:
          scoring(y_target=[1], y_predicted=[1], metric="test")
          assert False
      except AttributeError:
          assert True
  
file_path: mlxtend/mlxtend/evaluate/tests/test_scoring.py
imports: import numpy
  from mlxtend.evaluate import scoring
label_desc: Use image node_id 1 for calling a global function with example usage: test_metric_argument() without return types