code: def test_label(self):
      # SmOverlap only has 2 labels: ['1', '0']
      trans = sm_overlap.transform(sample1)
      self.assertTrue(trans[0].y.field_value in ["0", "1"])
  
imports: import unittest
  from textflint.input.component.sample.sm_sample import SMSample
  from textflint.generation.transformation.SM import Overlap
label_desc: Use image node_id 1 for calling the TestSmOverlap obj's underlying member method code with example usage: obj.test_label() without return types