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Whilst debugging a downloaded example script the following extract kept returning an error from the 3rd line which I could not resolve. I must confess I do not even understand how the construction between the curly brackets is supposed to work. Googling proved rather difficult.

    if_stats = psutil.net_if_stats()
    #remove loopback
    if_stats_filtered = {key: if_stats[key] for key, stat in if_stats.items() if "loopback" not in stat.flags}

if _stats contains the following:

{'lo': snicstats(isup=True, duplex=<NicDuplex.NIC_DUPLEX_UNKNOWN: 0>, speed=0, mtu=65536), 'wlan0': snicstats(isup=True, duplex=<NicDuplex.NIC_DUPLEX_UNKNOWN: 0>, speed=0, mtu=1460), 'eth0': snicstats(isup=True, duplex=<NicDuplex.NIC_DUPLEX_HALF: 1>, speed=10, mtu=1500)}

Error generated is:

if_stats_filtered = {key: if_stats[key] for key, stat in if_stats.items() if "loopback" not in stat.flags}

AttributeError: 'snicstats' object has no attribute 'flags'

Can anyone shed some light on what is happening please?

Digging deeper I think I understand why I am getting the error:

AttributeError: 'snicstats' object has no attribute 'flags'

snicstats is a namedtuple which is defined in an imported file named _common.py which forms part of psutil. My version of that script defines snicstats as follows:

snicstats = namedtuple('snicstats',
                   ['isup', 'duplex', 'speed', 'mtu',])

It seems a newer version of _common.py at github/psutil

redefines snicstats as follows:

snicstats = namedtuple('snicstats',
                   ['isup', 'duplex', 'speed', 'mtu', 'flags'])

I tried to upgrade psutil to the newer version but my system keeps returning that i have the most recent version.

What can I do?

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    {} is a dictionary. No one can say what the "problem" is from the scant code fragments you posted but this seems to be a programming question, NOT Pi specific. It might be clear if you used print(if_stats)
    – Milliways
    Commented Aug 2 at 8:44
  • I am not sure if the full code will help but one can see it all at: github.com/rm-hull/luma.examples/tree/master/examples The script is called "sys_info_extended.py". the if_stats content that I reproduced is actually the output of print(if_stat). I understand that if_stats_filtered is yet another dictionary, but how is its content being build up?
    – xuraax
    Commented Aug 2 at 12:55
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    The construct is a "dictionary comprehension" - like a "list comprehension" but producing a dictionary - see stackoverflow.com/a/14507637/2836621
    – Mark Setchell
    Commented Aug 2 at 13:41
  • NOTE the code fragment appears to be a complicated way of deleting a dictionary entry.
    – Milliways
    Commented Aug 2 at 23:16

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