code: def test_reader_from_pretrained(self):
      model = RealmReader.from_pretrained("google/realm-orqa-nq-reader")
      self.assertIsNotNone(model)
  
imports: import copy
  import unittest
  import numpy
  from transformers import RealmConfig, is_torch_available
  from transformers.testing_utils import require_torch, slow, torch_device
  from ...test_configuration_common import ConfigTester
  from ...test_modeling_common import ModelTesterMixin, floats_tensor, ids_tensor, random_attention_mask
label_desc: Use image node_id 11 for calling the RealmModelTest obj's underlying member method code with example usage: obj.test_reader_from_pretrained() without return types