code: def __init__(self):
      self._foo = None
      self._built = False
  
imports: import itertools
  from absl.testing import parameterized
  import numpy
  from sonnet.src import batch_norm
  from sonnet.src import initializers
  from sonnet.src import test_utils
  import tensorflow
label_desc: Use image node_id 1 to create a new TestMetric object  with example: obj = TestMetric()