docs: def before_scenario(context, scenario):
      """Prepare a fresh environment for each scenario."""
  
      # Prepare a new temporary directory.
      context.directory = testfixtures.TempDirectory(create=True)
      context.old_cwd = os.getcwd()
      context.new_cwd = context.directory.path
  
      # Move into our new working directory.
      os.chdir(context.new_cwd)