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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 on_options(self, req, resp, **kwargs):
 """Respond with JSON formatted resource description on OPTIONS request. Args: req (falcon.Request):
 Optional request object. Defaults to None. resp (falcon.Response):
 Optional response object. Defaults to None. kwargs (dict):
 Dictionary of values created by falcon from resource uri template. Returns: None .. versionchanged:: 0.2.0 Default ``OPTIONS`` responses include ``Allow`` header with list of allowed HTTP methods. """

        resp.set_header('Allow', ', '.join(self.allowed_methods()))
        resp.body = json.dumps(self.describe(req, resp))
        resp.content_type = 'application/json'