code: def test_rmse_series_subset_axis():
      rmse = pm.rmse(
          pd.Series([1, 3], ["a", "c"]),
          pd.Series([3, 4, 1], ["a", "b", "c"]),
      )
      assert rmse == approx(2)
  
imports: import numpy
  import pandas
  import os.path
  from pytest import approx, raises, mark, skip
  import lenskit.metrics.predict
  import lenskit.util.test
label_desc: Use image node_id 11 for calling a global function with example usage: test_rmse_series_subset_axis() without return types