docs: def append(table='filter', chain=None, rule=None, family='ipv4'):
      '''
      Append a rule to the specified table/chain.
  
      This function accepts a rule in a standard iptables command format,
          starting with the chain. Trying to force users to adapt to a new
          method of creating rules would be irritating at best, and we
          already have a parser that can handle it.
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' iptables.append filter INPUT \\
              rule='-m state --state RELATED,ESTABLISHED -j ACCEPT'
  
          IPv6:
          salt '*' iptables.append filter INPUT \\
              rule='-m state --state RELATED,ESTABLISHED -j ACCEPT' \\
              family=ipv6
      '''
      if not chain:
          return 'Error: Chain needs to be specified'
      if not rule:
          return 'Error: Rule needs to be specified'
  
      wait = '--wait' if _has_option('--wait', family) else ''
      returnCheck = check(table, chain, rule, family)
      if isinstance(returnCheck, bool) and returnCheck:
          return False
      cmd = '{0} {1} -t {2} -A {3} {4}'.format(
              _iptables_cmd(family), wait, table, chain, rule)
      out = __salt__['cmd.run'](cmd)
      return not out