code: def test_negative(self):
      X = np.array([[-1, 2], [3, 4]])
      with self.assertRaises(ValueError):
          CategoryShift().fit_transform(X)
  
file_path: auto-sklearn/test/test_pipeline/implementations/test_CategoryShift.py
imports: import numpy
  import scipy.sparse
  from autosklearn.pipeline.implementations.CategoryShift import CategoryShift
  import unittest
label_desc: Use image node_id 3 for calling the CategoryShiftTest obj's underlying member method code with example usage: obj.test_negative() without return types