cerebro.optstrategy() returns blank with maxcpus != 1

[Aditya Khurana]

Re: cerebro.optstrategy() failing with maxcpus > 1 (pickle error)

I am trying to run the sample code provided on backtrader quickstart guide for optimization. I only get the optimization output if I specify:

cerebro.run(maxcpus=1)

Any other value of maxcpus resulted in no log print. Omitting maxcpus parameter also resulted in no output. I have tried the following values:

2
3
4
None

Python 3.8.2
Backtrader 1.9.74.123

[Aditya Khurana]

@Aditya-Khurana same issue has been reported earlier by a user running Spyder.

I was using IDLE by Python. For me, multicore processing worked fine when I ran the file directly from command line.