code: def _create_paramters():
      split_years = testing.product(
          {
              "split": ["train", "trainval", "val"],
              "year": ["2007", "2012"],
          }
      )
      split_years += [{"split": "test", "year": "2007"}]
      params = testing.product_dict(
          split_years,
          [
              {"use_difficult": True, "return_difficult": True},
              {"use_difficult": True, "return_difficult": False},
              {"use_difficult": False, "return_difficult": True},
              {"use_difficult": False, "return_difficult": False},
          ],
      )
      return params
  
file_path: chainercv/tests/datasets_tests/voc_tests/test_voc_bbox_dataset.py
imports: import unittest
  import numpy
  from chainer import testing
  from chainer.testing import attr
  from chainer.testing import condition
  from chainercv.datasets import voc_bbox_label_names
  from chainercv.datasets import VOCBboxDataset
  from chainercv.utils import assert_is_bbox_dataset
label_desc: Use image node_id 1 for calling a global function with example usage: _create_paramters() and returns: params