code: def add_arguments_rnn_encoder_common(group):
      """Define common arguments for RNN encoder."""
      group.add_argument(
          "--etype",
          default="blstmp",
          type=str,
          choices=[
              "lstm",
              "blstm",
              "lstmp",
              "blstmp",
              "vgglstmp",
              "vggblstmp",
              "vgglstm",
              "vggblstm",
              "gru",
              "bgru",
              "grup",
              "bgrup",
              "vgggrup",
              "vggbgrup",
              "vgggru",
              "vggbgru",
          ],
          help="Type of encoder network architecture",
      )
      group.add_argument(
          "--elayers",
          default=4,
          type=int,
          help="Number of encoder layers",
      )
      group.add_argument(
          "--eunits",
          "-u",
          default=300,
          type=int,
          help="Number of encoder hidden units",
      )
      group.add_argument(
          "--eprojs",
          default=320,
          type=int,
          help="Number of encoder projection units",
      )
      group.add_argument(
          "--subsample",
          default="1",
          type=str,
          help="Subsample input frames x_y_z means "
          "subsample every x frame at 1st layer, "
          "every y frame at 2nd layer etc.",
      )
      return group
  
label_desc: Use image node_id 1 for calling a global function with example usage: add_arguments_rnn_encoder_common(group) and returns: group