code: def _get_config_dir():
      
      if 'SAWTOOTH_HOME' in os.environ:
          return os.path.join(os.environ['SAWTOOTH_HOME'], 'etc')
  
      if os.name == 'nt':
          base_dir = \
              os.path.dirname(os.path.dirname(os.path.abspath(sys.argv[0])))
          return os.path.join(base_dir, 'conf')
  
      return '/etc/sawtooth'
docs: Returns the sawtooth configuration directory based on the
      SAWTOOTH_HOME environment variable (if set) or OS defaults.