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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 serialize(self, data):
 """ Invoke the serializer These are common things for all serializers. Mostly, stuff to do with managing headers. The data passed in may not be reliable for much of anything. Conditionally, set the Content-Type header unless it has already been set. """


        if not self.resp.content_type:
            self.resp.set_header('Content-Type', getattr(self, 'MIMETYPE'))