code: def test_attributes(self):
      assert_equal(len(self.meta._attributes), 1)
  
      relational = list(self.meta._attributes.values())[0]
  
      assert_equal(relational.name, "attr_date_number")
      assert_equal(relational.type_name, "relational")
      assert_equal(len(relational.attributes), 2)
      assert_equal(relational.attributes[0].name, "attr_date")
      assert_equal(relational.attributes[0].type_name, "date")
      assert_equal(relational.attributes[1].name, "attr_number")
      assert_equal(relational.attributes[1].type_name, "numeric")
  
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_
  from pytest import raises
  from scipy.io.arff import loadarff
  from scipy.io.arff._arffread import read_header, ParseArffError
label_desc: Use image node_id 2 for calling the TestRelationalAttribute obj's underlying member method code with example usage: obj.test_attributes() without return types