code: def check(self):
      assert self.preprocess_event
      assert self.epoch_event > 10
      assert self.train_event
  
file_path: cuml/python/cuml/tests/test_internals_api.py
imports: import pytest
  from cuml.manifold import UMAP
  from cuml.internals import GraphBasedDimRedCallback
  from sklearn.datasets import load_digits
label_desc: Use image node_id 2 for calling the CustomCallback obj's underlying member method code with example usage: obj.check() without return types