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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 name_variants(self):
 """A list of namedtuples representing variants of the affiliation name with number of documents referring to this variant. """

        out = []
        variant = namedtuple('Variant', 'name doc_count')
        for var in chained_get(self._json, ['name-variants', 'name-variant'], []):
            new = variant(name=var['$'], doc_count=var.get('@doc-count'))
            out.append(new)
        return out