def METHOD_NAME(brain_vol_files: list[str]) -> None:
    runner = CliRunner()
    with runner.isolated_filesystem():
        r = runner.invoke(
            linear_regression,
            [
                "--nidm_file_list",
                ",".join(brain_vol_files),
                "--ml",
                "fs_000008 = DX_GROUP + http://uri.interlex.org/ilx_0100400",
                "--ctr",
                "DX_GROUP",
                "--regularization",
                "L2",
                "-o",
                "output.txt",
            ],
        )
        assert r.exit_code == 0
        out = Path("output.txt").read_text(encoding="utf-8")
    # check if model was read correctly
    assert "fs_000008 ~ ilx_0100400 + DX_GROUP" in out
    # check correct number of observations
    assert "No. Observations:                  53" in out
    # check lasso regression
    assert "Alpha with maximum likelihood (range: 1 to 700) = 699.000000" in out
    assert "Current Model Score = 0.017618" in out
    assert "ilx_0100400 	 -0.148397" in out
    assert "DX_GROUP 	 0.071356" in out
    assert "Intercept: 28.951297" in out