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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_section(self, *key):
 """ The recommended way of retrieving a section by key when extending configmanager's behaviour. """

        section = self._get_item_or_section(key)
        if not section.is_section:
            raise RuntimeError('{} is an item, not a section'.format(key))
        return section