Python 2.7 unpacking error

Question

I am getting the error message

badfilesdic = {k: v for k, v in badfilelist} ValueError: need more than 1 value to unpack

I am not sure how to fix it!

this is the code:

def badfiles(hasheddic, filesavedin ):

    print hasheddic
    print '\n'
    print filesavedin

    badfilelist = [s.split(' : ') for s in hasheddic]
    badcontentlist = [s.split(' : ') for s in filesavedin]
    badfilesdic = {k: v for k, v in badfilelist}
    badcontentdic = {k: v for v, k in badcontentlist}

    match = ""
    for hashval, filename in badcontentdic.iteritems():
        if filename in badfilesdic:
            match += (hashval + " File Extension:  " + badfilelist[filename]) + "\n"

    return match

Answer 1

You need to correct your code:

badfilelist = [s.split(':') for s in hasheddic]

then

badfilesdic = dict(badfilelist) # if you want to have a unique dict

or

badfilesdic = [{k:v} for k, v in badfilelist] # if you want to have a list of dicts

of maybe:

badfilesdic = tuple({k:v} for k, v in badfilelist) # if you want to have a tuple of dicts

or whatever you like. All you need is to unpack properly your variables.

Answer 2

The unpacking you are doing does not work as you expect. When you say k: v for k, v in hasheddic you are declaring a tuple of two elements (k,v) out of each element in hasheddic . If any of the strings exceed length 2, you get the unpacking error.

For example:

s = "hi hi".split()
for a, b in s:
    print a
    print b

Returns

h
i
h
i

If the string was, for example "foo bar", you would get the unpacking error for both "foo" and "bar".

If you are certain that your input string is well-formatted ( split always returns 2-element lists), you could do this instead:

{x[0]: x[1] for x in badfilelist}