code: def test_als_no_bias(m):
      algo = als.BiasedMF(20, iterations=10, bias=None, method=m)
      algo.fit(simple_df)
  
      assert algo.bias is None
      assert set(algo.user_index_) == set([10, 12, 13])
      assert set(algo.item_index_) == set([1, 2, 3])
      assert algo.user_features_.shape == (3, 20)
      assert algo.item_features_.shape == (3, 20)
  
      preds = algo.predict_for_user(10, [3])
      assert len(preds) == 1
  
imports: import logging
  import pickle
  from pickletools import dis
  from lenskit.algorithms import als
  from lenskit import util
  import pandas
  import numpy
  from seedbank import numpy_rng
  from pytest import approx, mark
  from lenskit.util import Stopwatch
  import lenskit.util.test
label_desc: Use image node_id 2 for calling a global function with example usage: test_als_no_bias(m) without return types