code: def test_list_of_series(self):
      a, b, y_true = self._get_raw_data()
  
      rf = [
          pd.Series(data=a, name="Alpha"),
          pd.Series(data=b, name="Beta"),
      ]
      target = _get_raw_MetricFrame()
      msg = "Feature lists must be of scalar types"
      with pytest.raises(ValueError) as execInfo:
          _ = target._process_features("Unused", rf, y_true)
      assert execInfo.value.args[0] == msg
  
imports: import numpy
  import pandas
  import pytest
  import fairlearn.metrics
  from .utils import _get_raw_MetricFrame
label_desc: Use image node_id 7 for calling the TestTwoFeatures obj's underlying member method code with example usage: obj.test_list_of_series() without return types