new_contents: from .pipe import pipe, expand_chunk, process_chunk
  
  
  def test_expand_chunk(fs):
      fs.CreateFile('file1')
      fs.CreateFile('file2')
  
      assert expand_chunk('ls') == ['ls']
      assert sorted(expand_chunk('file*')) == sorted(['file1', 'file2'])
  
  
  def test_process_chunk(fs):
      fs.CreateFile('file1')
      fs.CreateFile('file2')
  
      assert process_chunk('echo Hawken \n 26') == ['echo', 'Hawken', '26']
  
  
  def test_pipe():
      assert pipe('echo hi | cat') == (['cat'], b'hi\n')
  
subject: add tests for pipe