code: def _system_config_file():
      
      if sys.platform == 'win32':
          config_path = os.path.sep.join([_windows_system_appdata(),
                                          _APP_DIRNAME,
                                          _CONFIG_FILENAME])
      elif sys.platform.startswith('darwin'):
          config_path = os.path.sep.join([os.path.sep + 'Library', 'Preferences',
                                          _APP_DIRNAME, _CONFIG_FILENAME])
      else:
          config_path = os.path.sep.join(['', 'var', 'lib', _APP_DIRNAME,
                                          _CONFIG_FILENAME])
      return config_path
docs: Returns the path to the settings.cfg file. On Windows the file is
      located in the AppData/Local/envipyengine directory. On Unix, the file
      will be located in the ~/.envipyengine directory.
  
      :return: String specifying the full path to the settings.cfg file