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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_request_representer(self):
 """ Returns a representer for the content type specified in the request. :raises HTTPUnsupportedMediaType: If the specified content type is not supported. """

        try:
            mime_type = \
              get_registered_mime_type_for_string(self.request.content_type)
        except KeyError:
            # The client sent a content type we do not support (415).
            raise HTTPUnsupportedMediaType()
        return as_representer(self.context, mime_type)