code: def test_channel_reducer_trivial():
      array = np.zeros((10, 10, 10))
      for d in range(array.shape[-1]):
          array[:, :, d] = np.eye(10, 10)
  
      channel_reducer = ChannelReducer(n_components=2)
      channel_reducer.fit(array)
      reduced = channel_reducer.transform(array)
  
      assert reduced.shape == (10, 10, 2)
      # the hope here is that this was reduced to use only the first channel
      assert np.sum(reduced[:, :, 1]) == 0
  
imports: from __future__ import absolute_import, division, print_function
  import pytest
  import numpy
  from lucid.misc.channel_reducer import ChannelReducer
label_desc: Use image node_id 1 for calling a global function with example usage: test_channel_reducer_trivial() without return types