code: def test_return_self():
      no_users, no_items = (10, 100)
  
      train = sp.coo_matrix((no_users, no_items), dtype=np.int32)
  
      model = LightFM()
      assert model.fit_partial(train) is model
      assert model.fit(train) is model
  
imports: import numpy
  import pytest
  import scipy.sparse
  from lightfm.lightfm import LightFM
label_desc: Use image node_id 8 for calling a global function with example usage: test_return_self() without return types