Custom observer to track average returns across data feeds

[pratheek ponnuru]

Hello community.. :)
I am new here and to the tool. I am trying to create a custom observer that tracks portfolio returns and mean return across the universe being considered in multi feed strategy.

class AvgBench(bt.observer.Observer):
    lines = ('dreturn',)
    dreturn = collections.OrderedDict()
    
    def next(self):
        if self._owner._getminperstatus() < 0:

            self.lines.dreturn[0] = 0  # dummy line
            
            ret = 0
            for d in self._owner.datas:
                ret += d.l.close[-1] - d.l.close[0]
            ret /= len(self._owner.datas)
            date = self._owner.data.datetime.date(0)
            self.dreturn[date] = ret

I have a few questions -

1. Is this the best way to do this?
2. I dont think if self._owner._getminperstatus() < 0 is necessary here, please confirm.
3. How do I also add portfolio returns to the same observer?
   I know I can get the current value of the portfolio using self._owner.broker.get_value() but how can i get the returns?
4. If I add the default bt.observers.Benchmark and access the returns as stgy_run[0].observers.benchmark.tbench.rets I get a initial 0.0 which I do not get with my custom observer. Any thought?