code: def prepare_pixel_values(self):
      return floats_tensor(
          [
              self.batch_size,
              self.num_channels,
              self.image_size,
              self.image_size,
          ]
      )
  
imports: import unittest
  from parameterized import parameterized
  from transformers import BitsAndBytesConfig, IdeficsConfig, is_torch_available, is_vision_available
  from transformers.testing_utils import TestCasePlus, require_bitsandbytes, require_torch, require_torch_sdpa, require_vision, slow, torch_device
  from transformers.utils import cached_property
  from ...test_configuration_common import ConfigTester
  from ...test_modeling_common import ModelTesterMixin, floats_tensor, ids_tensor, random_attention_mask
  from ...test_pipeline_mixin import PipelineTesterMixin
label_desc: Use image node_id 8 for calling the IdeficsModelTester obj's underlying member method code with example usage: obj.prepare_pixel_values() and returns: floats_tensor