class_docstr: Test class for tf utility functions.
code: def test_get_target_ops_tau(self):
      var = tf.compat.v1.get_variable(
          "var", [1], initializer=tf.constant_initializer(1)
      )
      target_var = tf.compat.v1.get_variable(
          "target_var", [1], initializer=tf.constant_initializer(2)
      )
      self.sess.run(tf.compat.v1.global_variables_initializer())
      assert target_var.eval() == 2
      init_ops, update_ops = get_target_ops(
          [var], [target_var], tau=0.2
      )
      self.sess.run(update_ops)
      assert np.allclose(target_var.eval(), 1.8)
      self.sess.run(init_ops)
      assert np.allclose(target_var.eval(), 1)
  
file_path: garage/tests/garage/tf/test_functions.py
imports: import numpy
  import tensorflow
  from garage.tf import compute_advantages, get_target_ops
  from tests.fixtures import TfGraphTestCase
label_desc: Use image node_id 3 for calling the TestTensorUtil obj's underlying member method code with example usage: obj.test_get_target_ops_tau() without return types