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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 model2subs2seqs(self) -> Dict[str, Dict[str, List[str]]]: """A nested |collections.defaultdict| containing the model specific information provided by the XML `sequences` element. hland_v1 fluxes ['pc', 'tf'] hland_v1 states ['sm'] hstream_v1 states ['qjoints'] """

        model2subs2seqs = collections.defaultdict(
            lambda: collections.defaultdict(list))
        for model in self.find('sequences'):
            model_name = strip(model.tag)
            if model_name == 'node':
                continue
            for group in model:
                group_name = strip(group.tag)
                for sequence in group:
                    seq_name = strip(sequence.tag)
                    model2subs2seqs[model_name][group_name].append(seq_name)
        return model2subs2seqs