code: def test_invalid_knn_metric(knn_metric, create_X_y):
      X, y = create_X_y
      with pytest.raises(ValueError):
          ds = BaseDS(knn_metric=knn_metric)
          ds.fit(X, y)
  
imports: import numpy
  import pytest
  from sklearn.datasets import make_classification
  from sklearn.ensemble import RandomForestClassifier
  from sklearn.model_selection import train_test_split
  from sklearn.preprocessing import StandardScaler
  from deslib.base import BaseDS
  from deslib.dcs.a_posteriori import APosteriori
  from deslib.dcs.mcb import MCB
  from deslib.dcs.ola import OLA
  from deslib.dcs.rank import Rank
  from deslib.des import DESKL
  from deslib.des.des_knn import DESKNN
  from deslib.des.des_p import DESP
  from deslib.des.knora_e import KNORAE
  from deslib.des.knora_u import KNORAU
  from deslib.des.meta_des import METADES
label_desc: Use image node_id 2 for calling a global function with example usage: test_invalid_knn_metric(knn_metric, create_X_y) without return types