code: def test_import_faiss_mode():
      try:
          import sys
  
          sys.modules.pop("deslib.util.faiss_knn_wrapper")
      except Exception:
          pass
      with unittest.mock.patch.dict("sys.modules", {"faiss": None}):
          with pytest.raises(ImportError):
              BaseDS(knn_classifier="faiss")
  
imports: import unittest.mock
  from unittest.mock import Mock, MagicMock
  import numpy
  import pytest
  from sklearn.exceptions import NotFittedError
  from sklearn.neighbors import KNeighborsClassifier
  from deslib.base import BaseDS
  from deslib.util.dfp import frienemy_pruning_preprocessed
  from .conftest import create_base_classifier
label_desc: Use image node_id 11 for calling a global function with example usage: test_import_faiss_mode() without return types