def offset(self, time_delta):
        return self.as_of(self.as_of_date + Timedelta(time_delta))


# http://www.cmegroup.com/product-codes-listing/month-codes.html
Get the future chain for this root symbol with a given
dataset/ETHPy150Open quantopian/zipline/zipline/assets/futures.py/FutureChain.offset