code: def test_get_id__correct_DataFrame(self):
      df = pd.DataFrame(
          {"_value": [1, 2, 3, 4, 10, 11], "id": [1, 1, 1, 1, 2, 2]}
      )
      self.assertEqual(dataframe_functions.get_ids(df, "id"), {1, 2})
  
imports: import warnings
  from unittest import TestCase
  import numpy
  import pandas
  from pandas.testing import assert_frame_equal, assert_series_equal
  from tests.fixtures import warning_free
  from tsfresh import extract_relevant_features
  from tsfresh.feature_extraction.settings import MinimalFCParameters
  from tsfresh.utilities import dataframe_functions
label_desc: Use image node_id 1 for calling the GetIDsTestCase obj's underlying member method code with example usage: obj.test_get_id__correct_DataFrame() without return types