code: def test_fsvd_no_bias():
      algo = svd.FunkSVD(20, iterations=20, bias=None)
      algo.fit(simple_df)
  
      assert algo.bias is None
      assert algo.item_features_.shape == (3, 20)
      assert algo.user_features_.shape == (3, 20)
  
      preds = algo.predict_for_user(10, [3])
      assert len(preds) == 1
      assert preds.index[0] == 3
      assert all(preds.notna())
  
file_path: lkpy/tests/test_funksvd.py
imports: import logging
  import pickle
  from pathlib import Path
  import lenskit.algorithms.funksvd
  import pandas
  import numpy
  from pytest import approx, mark
  import lenskit.util.test
label_desc: Use image node_id 5 for calling a global function with example usage: test_fsvd_no_bias() without return types