Cant sort data by indicator value. Sorted function is not working as expected

[Eduardo De La Garza]

Hello. I have the following strategy but I cant manage to sort the data I have by a certain indicator value. It seems that the list always stays the same. Im not sure what I'm doing wrong. The pertinent code is in the rebalance_portfolio function. I also tried sorting the list in place with list.sort(lambda x: ...)

class SP500Rotation(bt.Strategy):
    params = dict(
        ...
    )

def __init__(self):
    self.inds = collections.defaultdict(dict)
    self.stocks = self.datas[1:]
    self.current_holdings = []

    self.idx_mav = bt.ind.SMA(self.data0, period=self.p.idx_period)
    for d in self.stocks:
        self.inds[d]['roc'] = bt.ind.RateOfChange(period=self.p.roc_period)
        self.inds[d]['rsi'] = bt.ind.RSI_SMA(
            safediv=True, period=self.p.rsi_period)

def notify_timer(self, timer, when, *args, **kwargs):
    self.rebalance_portfolio()

def rebalance_portfolio(self):
    inds = self.inds
    rankings = self.stocks
    rankings = sorted(rankings, key=lambda d: inds[d]["roc"][0], reverse=True) #This line
    rankings = rankings[:self.p.num_stocks]

    for holding in self.current_holdings:
        if holding not in rankings:
            self.close(holding)

    for d in rankings:
        if not self.getposition(d).size:
            self.order_target_percent(d, 1/self.p.num_stocks)

    self.current_holdings = rankings