def vests_to_rshares(self, vests, post_rshares=0, voting_power=STEEM_100_PERCENT, vote_pct=STEEM_100_PERCENT, subtract_dust_threshold=True, use_stored_data=True):
        """ Obtain the r-shares from vests

            :param number vests: vesting shares
            :param int post_rshares: rshares of post which is voted