code: def test_contains(self):
      self.assertTrue("a" in self.row)
      self.assertFalse("d" in self.row)
  
imports: import unittest
  from agate.mapped_sequence import MappedSequence
label_desc: Use image node_id 8 for calling the TestMappedSequence obj's underlying member method code with example usage: obj.test_contains() without return types