I'm trying to access the self.positions attribute from within the next method of a strategy. It works as expected with backbroker but throws Attribute Error when run with IBbroker.
Error: 'Lines_LineSeries_LineIterator_DataAccessor_Strateg' object has no attribute 'positions'

Here's my code:

from __future__ import (absolute_import, division, print_function,
                        unicode_literals)

from datetime import datetime, timedelta

import backtrader as bt


tat = "TATASTEEL_STK_NSE"
rel = "RELIANCE_STK_NSE"
itc = "ITC_STK_NSE"
stocks = [tat, rel, itc]


class MyStrategy(bt.Strategy):
    def __init__(self):
        pass

    def next(self):
        print(self.getpositionbyname(itc)) # 
        print(self.getpositionbyname(rel)) #  These 3 work well
        print(self.getpositionbyname(tat)) #
        print(self.positions) # Throws Attribute Error
        print(self.positionsbyname) # Throws Attribute Error

if __name__ == '__main__':
    cerebro = bt.Cerebro()
    store = bt.stores.IBStore(host="192.168.1.3", port=7497, _debug=False)
    datas = [store.getdata(dataname=stk, rtbar=True) for stk in stocks]

    for data in datas:
        cerebro.resampledata(data, timeframe=bt.TimeFrame.Minutes)

    cerebro.setbroker(store.getbroker())
    cerebro.addstrategy(MyStrategy)

    cerebro.run()

In debug mode the strategy attributes postitions and positionsbyname hold an str value containing the error message.

The Full Traceback looks something like this:

Although, separately requesting position for each datafeed using self.getpositionbyname() works seamlessly: