code: def get_dataset(data, dtype):
      """Load a dataset with a given dtype or return a previously loaded dataset"""
      key = (data.dataset, np.dtype(dtype).name)
      if key not in lazy_data:
          y = pd.read_csv(
              os.path.join(data_path, "{}.csv".format(data.dataset)),
              usecols=range(1, data.batch_size + 1),
              dtype=dtype,
          )
          y_train, y_test = train_test_split(
              y, test_size=data.n_test, shuffle=False
          )
          y_train_cudf = cudf.from_pandas(y_train).fillna(np.nan)
          y_test_cudf = cudf.from_pandas(y_test)
          if data.dataset_exog is not None:
              exog = pd.read_csv(
                  os.path.join(
                      data_path, "{}.csv".format(data.dataset_exog)
                  ),
                  usecols=range(1, data.n_exog * data.batch_size + 1),
                  dtype=dtype,
              )
              exog_past, exog_fut = train_test_split(
                  exog, test_size=data.n_test, shuffle=False
              )
              exog_past_cudf = cudf.from_pandas(exog_past).fillna(
                  np.nan
              )
              exog_fut_cudf = cudf.from_pandas(exog_fut)
          else:
              exog_past, exog_past_cudf, exog_fut, exog_fut_cudf = [
                  None
              ] * 4
          lazy_data[key] = (
              y_train,
              y_train_cudf,
              y_test,
              y_test_cudf,
              exog_past,
              exog_past_cudf,
              exog_fut,
              exog_fut_cudf,
          )
      return lazy_data[key]
  
imports: from cuml.testing.utils import stress_param
  from cuml.internals.input_utils import input_to_host_array
  import cuml.tsa.arima
  from cuml.internals.safe_imports import gpu_only_import
  import statsmodels.api
  from sklearn.model_selection import train_test_split
  from cuml.internals.safe_imports import cpu_only_import_from
  import warnings
  import os
  import pytest
  from cuml.internals.safe_imports import cpu_only_import
label_desc: Use image node_id 2 for calling a global function with example usage: get_dataset(data, dtype) and returns: lazy_data