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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 _add_comment(self, thing_id, text):
 """Comment on the given thing with the given text. :returns: A Comment object for the newly created comment. """

        def add_comment_helper(self, thing_id, text):
            data = {'thing_id': thing_id,
                    'text': text}
            retval = self.request_json(self.config['comment'], data=data,
                                       retry_on_error=False)
            return retval

        if thing_id.startswith(self.config.by_object[objects.Message]):
            decorator = decorators.restrict_access(scope='privatemessages')
        else:
            decorator = decorators.restrict_access(scope='submit')
        retval = decorator(add_comment_helper)(self, thing_id, text)
        # REDDIT: reddit's end should only ever return a single comment
        return retval['data']['things'][0]