old_contents: import os
  
  from .. import run_nbgrader
  from .base import BaseTestApp
  
  
  class TestNbGraderGenerateConfig(BaseTestApp):
  
      def test_help(self):
          """Does the help display without error?"""
          run_nbgrader(["generate_config", "--help-all"])
  
      def test_generate_config(self):
          """Is the config file properly generated?"""
  
          # it already exists, because we create it in conftest.py
          os.remove("nbgrader_config.py")
  
          # try recreating it
          run_nbgrader(["generate_config"])
          assert os.path.isfile("nbgrader_config.py")
  
          # does it fail if it already exists?
          run_nbgrader(["generate_config"], retcode=1)
  
new_contents: import os
  
  from .. import run_nbgrader
  from .base import BaseTestApp
  
  
  class TestNbGraderGenerateConfig(BaseTestApp):
  
      def test_help(self):
          """Does the help display without error?"""
          run_nbgrader(["generate_config", "--help-all"])
  
      def test_generate_config(self):
          """Is the config file properly generated?"""
  
          # it already exists, because we create it in conftest.py
          os.remove("nbgrader_config.py")
  
          # try recreating it
          run_nbgrader(["generate_config"])
          assert os.path.isfile("nbgrader_config.py")
  
          with open("nbgrader_config.py") as f:
              contents = f.read()
  
          # This was missing in issue #1089
          assert "AssignLatePenalties" in contents
  
          # does it fail if it already exists?
          run_nbgrader(["generate_config"], retcode=1)
  
subject: Add assertion for issue gh-1089