old_contents: import pep8
  import os
  
  
  def test_pep8_conformance():
      """Test source code for PEP8 conformance"""
      pep8style = pep8.StyleGuide(max_line_length=120)
      report = pep8style.options.report
      report.start()
      pep8style.input_dir(os.path.join('..', 'xylem'))
      report.stop()
      assert report.total_errors == 0, "Found '{0}' code style errors (and warnings).".format(report.total_errors)
  
new_contents: import pep8
  import os
  
  
  def test_pep8_conformance():
      """Test source code for PEP8 conformance"""
      pep8style = pep8.StyleGuide(max_line_length=120)
      report = pep8style.options.report
      report.start()
      pep8style.input_dir(os.path.join('xylem'))
      report.stop()
      assert report.total_errors == 0, "Found '{0}' code style errors (and warnings).".format(report.total_errors)
  
subject: Fix relative path to only test xylem source directory.