code: def test_variables_control_dependencies(ray_start_2_cpus):
      # Creates a network and appends a momentum optimizer.
      sess = tf.Session()
      loss, init, _, _ = make_linear_network()
      minimizer = tf.train.MomentumOptimizer(0.9, 0.9).minimize(loss)
      net_vars = ray.experimental.tf_utils.TensorFlowVariables(
          minimizer, sess
      )
      sess.run(init)
  
      # Tests if all variables are properly retrieved, 2 variables and 2
      # momentum variables.
      assert len(net_vars.variables.items()) == 4
  
imports: from numpy.testing import assert_almost_equal
  import ray
  import ray.experimental.tf_utils
  from ray.rllib.utils.framework import try_import_tf
label_desc: Use image node_id 8 for calling a global function with example usage: test_variables_control_dependencies(ray_start_2_cpus) without return types