docs: def _regex_iptables_save(cmd_output, filters=None):
      '''
      Return string with `save_filter` regex entries removed.  For example:
  
      If `filters` is not provided, it will be pulled from minion config,
      minion grains, minion pillar, or master config. Default return value
      if no filters found is the original cmd_output string.
  
      .. code-block:: python
  
          _regex_iptables_save(cmd_output, ['-A DOCKER*'])
      '''
      # grab RE compiled filters from context for performance
      if 'iptables.save_filters' not in __context__:
          __context__['iptables.save_filters'] = []
          for pattern in filters or _conf_save_filters():
              try:
                  __context__['iptables.save_filters']\
                      .append(re.compile(pattern))
              except re.error as e:
                  log.warning('Skipping regex rule: \'%s\': %s',
                              pattern, e)
                  continue
  
      if __context__['iptables.save_filters']:
          # line by line get rid of any regex matches
          _filtered_cmd_output = \
              [line for line in cmd_output.splitlines(True)
               if not any(reg.search(line) for reg
                          in __context__['iptables.save_filters'])]
          return ''.join(_filtered_cmd_output)
  
      return cmd_output