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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_header(self):
 """Get the header value from the response. :return: a future contains the deserialized value of header """

        raw_header = yield get_arg(self, 1)
        if not self.serializer:
            raise tornado.gen.Return(raw_header)
        else:
            header = self.serializer.deserialize_header(raw_header)
            raise tornado.gen.Return(header)