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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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)