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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 prepare(self):
 """Prepare the incoming request, checking to see the request is sending JSON content in the request body. If so, the content is decoded and assigned to the json_arguments attribute. """

        super(RequestHandler, self).prepare()
        if self.request.headers.get('content-type', '').startswith(self.JSON):
            self.request.body = escape.json_decode(self.request.body)