Question

I’m surprised that I get an error when checking if a certain value in in my dictionary like this:

if src in mac_dict:

I have filled up my dictionaary like this:

data = database.get(mac, "get_nodelist", version=1)
if data:
    fh = StringIO(data)
    version = ord(fh.read(1))
    length = ord2b(fh.read(2))
    length = length / 8
    macs = {}
    for i in xrange(0,length):
        mac = fh.read(6)[-3:]
        tdm = ord2b(fh.read(2))
        macs[mac] = tdm
        print hexlify(mac) + " - " + str(tdm)
    fh.close()
    fh = open("macs.bin","wb")
    pickle.dump(macs,fh)
    fh.close()
    return macs

data contains 6 Bytes of mac adresses plus 2 Bytes of tdm in sa row. They seem to be decoded properly with the print statement but when I want to check if src (in binary) is part of mac_dict, my script throws an exception – even tho I definitely should be in there.. any hints?

Thank you!
Ron

Answer 1

You will need to do this to check if a value is present:

if src in mac_dict.values():

What your code is doing is checking if src is already in use as a key. The dictionary class also has an equivalent method:

if mac_dict.has_key(src):