docs: def flush(table='filter', chain='', family='ipv4'):
      '''
      Flush the chain in the specified table, flush all chains in the specified
      table if chain is not specified.
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' nftables.flush filter
  
          salt '*' nftables.flush filter input
  
          IPv6:
          salt '*' nftables.flush filter input family=ipv6
      '''
      ret = {'comment': 'Failed to flush rules from chain {0} in table {1}.'.format(chain, table),
             'result': False}
  
      res = check_table(table, family=family)
      if not res['result']:
          return res
  
      nft_family = _NFTABLES_FAMILIES[family]
  
      if chain:
          res = check_chain(table, chain, family=family)
          if not res['result']:
              return res
          cmd = '{0} flush chain {1} {2} {3}'.\
                format(_nftables_cmd(), nft_family, table, chain)
          comment = 'from chain {0} in table {1} in family {2}.'.\
                    format(chain, table, family)
      else:
          cmd = '{0} flush table {1} {2}'.\
                  format(_nftables_cmd(), nft_family, table)
          comment = 'from table {0} in family {1}.'.\
                    format(table, family)
      out = __salt__['cmd.run'](cmd, python_shell=False)
  
      if len(out) == 0:
          ret['result'] = True
          ret['comment'] = 'Flushed rules {0}'.format(comment)
      else:
          ret['comment'] = 'Failed to flush rules {0}'.format(comment)
      return ret