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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 _set_extensions(self):
 """ Sets common named extensions to private attributes and creates a list of critical extensions """


        self._critical_extensions = set()

        for extension in self['single_extensions']:
            name = extension['extn_id'].native
            attribute_name = '_%s_value' % name
            if hasattr(self, attribute_name):
                setattr(self, attribute_name, extension['extn_value'].parsed)
            if extension['critical'].native:
                self._critical_extensions.add(name)

        self._processed_extensions = True