code: def testUnknownHparams(self):
      with self.assertRaisesRegexp(KeyError, "never registered"):
          registry.hparams("not_registered")
      with self.assertRaisesRegexp(KeyError, "never registered"):
          registry.ranged_hparams("not_registered")
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from tensor2tensor.utils import registry
  from tensor2tensor.utils import t2t_model
  import tensorflow.compat.v1
label_desc: Use image node_id 4 for calling the HParamRegistryTest obj's underlying member method code with example usage: obj.testUnknownHparams() without return types