code: def test_shuffled_x(self):
      # when
  
      batch_x = [4, 2, 10, 28]
      epoch_x = [np.nan] + [1, 2, 21]
      odd_x = [21, 10, 15, 4]
      detached_x = [3, 5, 9] + [np.nan]
  
      batch_y = [7, 2, 9, 1]
      epoch_y = [np.nan, 3, 5, 9]
      odd_y = [21, 15, 4, 3]
      detached_y = [1, 5, 12, np.nan]
  
      df = pd.DataFrame(
          {
              "x_batch_channel": batch_x,
              "y_batch_channel": batch_y,
              "x_epoch_channel": epoch_x,
              "y_epoch_channel": epoch_y,
              "x_odd_channel": odd_x,
              "y_odd_channel": odd_y,
              "x_detached_channel": detached_x,
              "y_detached_channel": detached_y,
          },
          dtype=float,
      )
  
      expected_result = pd.DataFrame(
          {
              "x": [1, 2, 3, 4, 5, 9, 10, 15, 21, 28],
              "batch_channel": [
                  np.nan,
                  2,
                  np.nan,
                  7,
                  np.nan,
                  np.nan,
                  9,
                  np.nan,
                  np.nan,
                  1,
              ],
              "epoch_channel": [
                  3,
                  5,
                  np.nan,
                  np.nan,
                  np.nan,
                  np.nan,
                  np.nan,
                  np.nan,
                  9,
                  np.nan,
              ],
              "odd_channel": [
                  np.nan,
                  np.nan,
                  np.nan,
                  3,
                  np.nan,
                  np.nan,
                  15,
                  4,
                  21,
                  np.nan,
              ],
              "detached_channel": [
                  np.nan,
                  np.nan,
                  1,
                  np.nan,
                  5,
                  12,
                  np.nan,
                  np.nan,
                  np.nan,
                  np.nan,
              ],
          },
          dtype=float,
      )
      expected_result = sort_df_by_columns(expected_result)
  
      # then
      result = align_channels_on_x(df)
      result = sort_df_by_columns(result)
  
      assert_frame_equal(result, expected_result)
  
imports: import unittest
  import numpy
  import pandas
  from pandas.testing import assert_frame_equal
  from neptune.common.utils import align_channels_on_x, as_list, get_channel_name_stems, map_keys, map_values, merge_dataframes
  from tests.unit.neptune.legacy.random_utils import sort_df_by_columns
label_desc: Use image node_id 2 for calling the TestAlignChannelsOnX obj's underlying member method code with example usage: obj.test_shuffled_x() without return types