code: def test_als_predict_bad_item():
      algo = als.ImplicitMF(20, iterations=10)
      algo.fit(simple_df)
  
      preds = algo.predict_for_user(10, [4])
      assert len(preds) == 1
      assert preds.index[0] == 4
      assert np.isnan(preds.loc[4])
  
imports: import logging
  from lenskit import util
  from lenskit.algorithms import als
  import pandas
  import numpy
  from scipy import stats
  import binpickle
  from seedbank import numpy_rng
  from pytest import mark, approx
  import lenskit.util.test
  from lenskit.algorithms import Recommender
  from lenskit.util import Stopwatch
label_desc: Use image node_id 7 for calling a global function with example usage: test_als_predict_bad_item() without return types