Make a temporary directory.

def make_tmp_dir(suffix="", prefix="tmp", dir=None):  # pylint: disable=redefined-builtin
  """Make a temporary directory."""
  if dir is None:
    return tempfile.mkdtemp(suffix, prefix, dir)
  else:
    while True:
      rand_term = random.randint(1, 9999)
      tmp_dir = os.path.join(dir, "%s%d%s" % (prefix, rand_term, suffix))
      if tf.gfile.Exists(tmp_dir):
        continue
      tf.gfile.MakeDirs(tmp_dir)
      break
    return tmp_dir