code: def forward(
      self,
      input_ids,
      attention_mask,
      num_beams,
      max_length,
      decoder_start_token_id,
  ):
      pad_token_id = self.config.pad_token_id
      bos_token_id = self.config.bos_token_id
      eos_token_id = self.config.eos_token_id
  
      # special case if pad_token_id is not defined
      if pad_token_id is None and eos_token_id is not None:
          # logger.warning(f"Setting `pad_token_id` to `eos_token_id`:{eos_token_id} for open-end generation.")
          pad_token_id = eos_token_id
  
      encoder_output = self._encoder_forward(input_ids, attention_mask)
  
      input_ids = self._prepare_decoder_input_ids_for_generation(
          input_ids,
          decoder_start_token_id=decoder_start_token_id,
          bos_token_id=bos_token_id,
      )
  
      batch_size = input_ids.shape[0]
  
      length_penalty = self.config.length_penalty
      num_return_sequences = self.config.num_return_sequences
      early_stopping = True
  
      self.beam_scorer.init(
          batch_size=batch_size,
          max_length=max_length,
          num_beams=num_beams,
          device=self.device,
          length_penalty=length_penalty,
          do_early_stopping=early_stopping,
          num_beam_hyps_to_keep=num_return_sequences,
      )
  
      (
          input_ids,
          attention_mask,
          encoder_output,
      ) = self._expand_inputs_for_generation(
          input_ids,
          attention_mask,
          encoder_output,
          expand_size=num_beams,
      )
  
      return self.beam_search(
          input_ids=input_ids,
          encoder_output=encoder_output,
          attention_mask=attention_mask,
          num_beams=num_beams,
          max_length=max_length,
          pad_token_id=pad_token_id,
          eos_token_id=eos_token_id,
      )
  
imports: import copy
  import itertools
  from typing import List, Optional, Tuple
  import torch
  import torch.nn.functional
  from transformers import BartConfig
  from transformers.generation_utils import GenerationMixin
label_desc: Use image node_id 7 for calling the BARTBeamSearchGenerator obj's underlying member method code with example usage: obj.forward(input_ids, attention_mask, num_beams, max_length, decoder_start_token_id) and returns: self