code: def test_data_is_zero(self):
      d = tf_metrics.TFDeque(3, tf.int32, shape=(2,))
      self.evaluate(tf.compat.v1.global_variables_initializer())
      values = self.evaluate(d.data)
      self.assertAllEqual((0, 2), values.shape)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import parameterized
  import tensorflow
  from tf_agents.metrics import tf_metrics
  from tf_agents.specs import tensor_spec
  from tf_agents.trajectories import trajectory
  from tensorflow.python.eager import context
label_desc: Use image node_id 2 for calling the TFShapedDequeTest obj's underlying member method code with example usage: obj.test_data_is_zero() without return types