docstr: Verify that depth growing happens.
docstr_tok: ["Verify","that","depth","growing","happens","."]
code: def test_grow(self):
      """Verify that depth growing happens."""
      nblocks = 4
      blocks_to_use = np.arange(1, nblocks + 1)
      depth = 9
      ntrials = 10 * nblocks * depth
      np.random.seed(0)
      architectures = np.random.randint(
          1, nblocks + 1, size=(ntrials, depth)
      )
      losses = np.sum(architectures, axis=1)
      expected_best = np.repeat(min(blocks_to_use), depth)
  
      best_nogrow = _get_suggestion(
          architectures, blocks_to_use, losses, grow=False
      )
      self.assertAllEqual(best_nogrow, expected_best)
  
      best_grow = _get_suggestion(
          architectures, blocks_to_use, losses, grow=True
      )
      self.assertAllEqual(
          best_grow,
          np.append(expected_best, block_builder.BlockType[NEW_BLOCK]),
      )
  
imports: from absl.testing import parameterized
  import mock
  from model_search import block_builder
  from model_search import hparam
  from model_search.metadata import trial
  from model_search.proto import phoenix_spec_pb2
  from model_search.search import linear_model
  from model_search.search import test_utils
  import numpy
  import tensorflow.compat.v2
label_desc: Use image node_id 8 for calling the LinearModelTest obj's underlying member method code with example usage: obj.test_grow() without return types