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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 get_unknown_opttrans_attr(path):
 """Utility method that gives a `dict` of unknown and unsupported optional transitive path attributes of `path`. Returns dict: <key> - attribute type code, <value> - unknown path-attr. """

    path_attrs = path.pathattr_map
    unknown_opt_tran_attrs = {}
    for _, attr in path_attrs.items():
        if (isinstance(attr, BGPPathAttributeUnknown) and
                attr.flags & (BGP_ATTR_FLAG_OPTIONAL |
                              BGP_ATTR_FLAG_TRANSITIVE)) or \
                isinstance(attr, BGPPathAttributeAs4Path) or \
                isinstance(attr, BGPPathAttributeAs4Aggregator):
            unknown_opt_tran_attrs[attr.type] = attr

    return unknown_opt_tran_attrs