class_docstr: A wrapper class for testing PPOTrainer
class_docstr_tok: ["A","wrapper","class","for","testing","PPOTrainer"]
code: def test_generation(self):
      dummy_dataset = self._init_dummy_dataset()
  
      model = AutoModelForCausalLMWithValueHead.from_pretrained("gpt2")
      tokenizer = AutoTokenizer.from_pretrained("gpt2")
  
      ppo_trainer = PPOTrainer(
          config=self.ppo_config,
          model=model,
          ref_model=None,
          tokenizer=tokenizer,
          dataset=dummy_dataset,
      )
  
      input_texts = ["this is a test", "this is another, longer test"]
  
      generation_kwargs = {
          "do_sample": False,
          "max_new_tokens": 4,
          "pad_token_id": tokenizer.eos_token_id,
      }
  
      tokenizer.pad_token = tokenizer.eos_token
  
      model_inputs = [
          tokenizer(txt, return_tensors="pt").input_ids.squeeze()
          for txt in input_texts
      ]
  
      generations_batched = ppo_trainer.generate(
          model_inputs, batch_size=2, **generation_kwargs
      )
      generations_batched = tokenizer.batch_decode(generations_batched)
  
      generations_single = [
          ppo_trainer.generate(inputs, **generation_kwargs).squeeze()
          for inputs in model_inputs
      ]
      generations_single = tokenizer.batch_decode(generations_single)
  
      self.assertEqual(generations_single, generations_batched)
  
imports: import copy
  import fnmatch
  import gc
  import re
  import tempfile
  import unittest
  import pytest
  import torch
  from huggingface_hub import HfApi, HfFolder, delete_repo
  from parameterized import parameterized
  from pytest import mark
  from requests.exceptions import HTTPError
  from transformers import AutoTokenizer
  from trl import AutoModelForCausalLMWithValueHead, AutoModelForSeq2SeqLMWithValueHead, PPOConfig, PPOTrainer, set_seed
  from trl.core import respond_to_batch
  from .testing_constants import CI_HUB_ENDPOINT, CI_HUB_USER, CI_HUB_USER_TOKEN
  from .testing_utils import require_peft, require_torch_multi_gpu
label_desc: Use image node_id 26 for calling the PPOTrainerTester obj's underlying member method code with example usage: obj.test_generation() without return types