docs: def nla_parse_nested(tb, maxtype, nla, policy):
      """Create attribute index based on nested attribute.
  
      https://github.com/thom311/libnl/blob/libnl3_2_25/lib/attr.c#L885
  
      Feeds the stream of attributes nested into the specified attribute to nla_parse().
  
      Positional arguments:
      tb -- dictionary to be filled (maxtype+1 elements).
      maxtype -- maximum attribute type expected and accepted (integer).
      nla -- nested attribute (nlattr class instance).
      policy -- attribute validation policy.
  
      Returns:
      0 on success or a negative error code.
      """
      return nla_parse(tb, maxtype, nlattr(nla_data(nla)), nla_len(nla), policy)