def METHOD_NAME(self, model_version):
    np = pytest.importorskip("numpy")
    pytest.importorskip("sklearn")
    from sklearn.linear_model import LogisticRegression
    key = "coef"
    classifier = LogisticRegression()
    classifier.fit(np.random.random((36, 12)), np.random.random(36).round())
    original_coef = classifier.coef_
    model_version.log_artifact(key, original_coef)
    # retrieve the artifact:
    retrieved_coef = model_version.get_artifact(key)
    assert np.array_equal(retrieved_coef, original_coef)
    artifact_msg = model_version._get_artifact_msg(key)
    assert artifact_msg.key == key
    assert artifact_msg.filename_extension == "pkl"
    # Overwrite should work:
    new_classifier = LogisticRegression()
    new_classifier.fit(np.random.random((36, 12)), np.random.random(36).round())
    model_version.log_artifact(key, new_classifier.coef_, overwrite=True)
    retrieved_coef = model_version.get_artifact(key)
    assert np.array_equal(retrieved_coef, new_classifier.coef_)
    # when overwrite = false, overwriting should fail
    with pytest.raises(ValueError) as excinfo:
        model_version.log_artifact(key, new_classifier.coef_)
    assert "The key has been set" in str(excinfo.value)