code: def test_apply_function_evk():
      """Check the apply_function method for evoked data."""
      # create fake evoked data to use for checking apply_function
      data = np.random.rand(10, 1000)
      info = create_info(10, 1000.0, "eeg")
      evoked = EvokedArray(data, info)
      evoked_data = evoked.data.copy()
      # check apply_function channel-wise
  
      def fun(data, multiplier):
          return data * multiplier
  
      mult = -1
      applied = evoked.apply_function(fun, n_jobs=None, multiplier=mult)
      assert np.shape(applied.data) == np.shape(evoked_data)
      assert np.equal(applied.data, evoked_data * mult).all()
  
imports: import pickle
  from copy import deepcopy
  from pathlib import Path
  import numpy
  import pytest
  from numpy.testing import assert_allclose, assert_array_almost_equal, assert_array_equal, assert_equal
  from scipy import fftpack
  from mne import Epochs, EpochsArray, combine_evoked, create_info, equalize_channels, pick_types, read_events, read_evokeds, write_evokeds
  from mne._fiff.constants import FIFF
  from mne.evoked import Evoked, EvokedArray, _get_peak
  from mne.io import read_raw_fif
  from mne.utils import grand_average
label_desc: Use image node_id 27 for calling a global function with example usage: test_apply_function_evk() and returns: unknown