def _ListRunTargets(test_bench):
  """List the run targets in the test bench.

  Args:
    test_bench: a test bench
  Returns:
    a sorted list of run_target names
  """
  groups = test_bench.host.groups
  run_targets = []
  for group in groups:
    for run_target in group.run_targets:
      run_targets.append(run_target.name)
  return sorted(run_targets)