def METHOD_NAME():
    original_df = DATAFRAME_WITH_STATIC.copy()
    splitter = MultiWindowSplitter()
    prediction_length = 7
    train_data, val_data = splitter.split(ts_dataframe=original_df, prediction_length=prediction_length)
    for item_id in train_data.item_ids:
        assert (train_data.static_features.loc[item_id] == original_df.static_features.loc[item_id]).all()
    for item_id in val_data.item_ids:
        original_item_id, _, _ = get_original_item_id_and_slice(item_id)
        assert (val_data.static_features.loc[item_id] == original_df.static_features.loc[original_item_id]).all()