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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_callback(self, renderer_context):
 """ Determine the name of the callback to wrap around the json output. """

        request = renderer_context.get('request', None)
        params = request and get_query_params(request) or {}
        return params.get(self.callback_parameter, self.default_callback)