code: def testContains(self):
      st = schema.Struct(
          ("a", schema.Scalar()),
          (
              "b",
              schema.Struct(
                  (
                      "c",
                      schema.Struct(
                          ("d", schema.Scalar()),
                      ),
                  ),
              ),
          ),
      )
      self.assertTrue("a" in st)
      self.assertTrue("b:c" in st)
      self.assertTrue("b:c:d" in st)
      self.assertFalse("" in st)
      self.assertFalse("x" in st)
      self.assertFalse("b:c:x" in st)
      self.assertFalse("b:c:d:x" in st)
  
imports: from caffe2.python import core, schema
  import numpy
  import unittest
  import pickle
  import random
label_desc: Use image node_id 22 for calling the TestDB obj's underlying member method code with example usage: obj.testContains() without return types