Trying to understand condensed Python

2017-01-27

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Question

I'm trying to understand how this code lays out in long format

proposed = dict((k, v) for k, v in args.iteritems() if v is not None)

The best I can come up with is the following, but it doesn't work:

for k,v in args.iteritems():
    print "value of v is: %s" % v
    if v is not None:
    proposed = dict(k,v)

However it throws the following error:

TypeError: dict expected at most 1 arguments, got 2

Try:

proposed=dict()
for k,v in args.iteritems():
  print "value of v is: %s" % v
  if v is not None:
    proposed[k] = v #This is the part you got wrong