code: def vintage_dates(self,series_id=None,response_type=None,params=None):
          
          path = '/series/vintagedates?'
          params['series_id'] = series_id
          response_type = response_type if response_type else self.response_type
          if response_type != 'xml': params['file_type'] = 'json'
          response = _get_request(self.url_root,self.api_key,path,response_type,params,self.ssl_verify)
          return response
docs: Function to request the dates in history when a series' data values were
          revised or new data values were released. Vintage dates are the release dates
          for a series excluding release dates when the data for the series did not change.
          `<https://research.stlouisfed.org/docs/api/fred/series_vintagedates.html>`_
  
          :arg int series_id: The id for a series. Required.
          :arg str response_type: File extension of response. Options are 'xml', 'json',
                          'dict','df','numpy','csv','tab,'pipe'. Required.
          :arg str realtime_start: The start of the real-time period. Format "YYYY-MM-DD"
          :arg str realtime_end: The end of the real-time period. Format "YYYY-MM-DD"
          :arg int limit: The maximum number of results to return. Options 1 to 1000
          :arg int offset: Data offset. Options >=0
          :arg str sort_order: Sort results by vintage_date. Options are 'asc','desc'
          :arg bool ssl_verify: To verify HTTPs.