code: def test_data(self):
      dtype_instance = [
          ("attr_date", "datetime64[D]"),
          ("attr_number", np.float_),
      ]
  
      expected = [
          np.array(
              [("1999-01-31", 1), ("1935-11-27", 10)],
              dtype=dtype_instance,
          ),
          np.array(
              [("2004-12-01", 2), ("1942-08-13", 20)],
              dtype=dtype_instance,
          ),
          np.array([("1817-04-28", 3)], dtype=dtype_instance),
          np.array(
              [
                  ("2100-09-10", 4),
                  ("1957-04-17", 40),
                  ("1721-01-14", 400),
              ],
              dtype=dtype_instance,
          ),
          np.array([("2013-11-30", 5)], dtype=dtype_instance),
          np.array([("1631-10-15", 6)], dtype=dtype_instance),
      ]
  
      for i in range(len(self.data["attr_date_number"])):
          assert_array_equal(
              self.data["attr_date_number"][i], expected[i]
          )
  
imports: import datetime
  import os
  import sys
  from os.path import join
  from io import StringIO
  import numpy
  from numpy.testing import assert_array_almost_equal, assert_array_equal, assert_equal, assert_
  import pytest
  from pytest import raises
  from scipy.io.arff.arffread import loadarff
  from scipy.io.arff.arffread import read_header, ParseArffError
label_desc: Use image node_id 3 for calling the TestRelationalAttribute obj's underlying member method code with example usage: obj.test_data() without return types