code: def test_topn_config():
      pred = basic.Memorized(simple_df)
      rec = basic.TopN(pred)
  
      rs = str(rec)
      assert rs.startswith("TopN/")
  
file_path: lkpy/tests/test_topn_recs.py
imports: from lenskit.algorithms import basic
  from lenskit.algorithms import bias
  import pandas
  import numpy
  import lenskit.util.test
  from pytest import approx
label_desc: Use image node_id 2 for calling a global function with example usage: test_topn_config() without return types