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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(self, key, section=None, default=_onion_dict_guard):
 """Try to get the key from each dict in turn. If you specify the optional section it looks there first. """

        if section is not None:
            section_dict = self.__sections.get(section, {})
            if key in section_dict:
                return section_dict[key]
        for d in self.__dictionaries:
            if key in d:
                return d[key]
        if default is _onion_dict_guard:
            raise KeyError(key)
        else:
            return default