code: def sample_data():
      # Sample data for testing
      x = np.array([np.random.rand(100)] * 8)
      y = np.array([0, 0, 0, 0, 1, 1, 1, 1])
      groups = np.array(["A", "A", "B", "B", "A", "A", "B", "B"])
      return x, y, groups
  
file_path: pykale/tests/evaluate/test_cross_validation.py
imports: import numpy
  import pytest
  from sklearn.dummy import DummyClassifier
  from kale.evaluate import cross_validation
  from kale.pipeline.multi_domain_adapter import CoIRLS
label_desc: Use image node_id 1 for calling a global function with example usage: sample_data() and returns: x,  y,  groups