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Python Python Collections (Retired) Tuples Combo

Posted by csj
csj
12,678 Points

I can't understand why this wont pass

I've been looking at the python documentation for .zip()

And if I write this script 

def combo(x, y):
    zipped = zip(x, y)
    print(zipped)

x = [1, 2, 3]
y = "abc"
combo(x, y)

and run it in Terminal i get this output:

$ python zippy.py 
[(1, 'a'), (2, 'b'), (3, 'c')]

Looks pretty correct to me, but why wont it pass in Workspaces?

zippy.py 
# combo([1, 2, 3], 'abc')
# Output:
# [(1, 'a'), (2, 'b'), (3, 'c')]
# If you use .append(), you'll want to pass it a tuple of new values.
def combo(x, y):
    zipped = zip(x, y)
    return zipped
csj
csj
12,678 Points

Just for future reference. A solution for using zip() in Python 3:

def combo(x, y):
    output = list(zip(x, y))
    return output

3 Answers

Ryan S
Ryan S
27,276 Points
Ryan S
Ryan S
27,276 Points

Just looking at the zip docs, I think the issue is that the zip() function is a generator, so just assigning it to a variable will not actually call it like a regular function. In order to make use of a generator you'd need to call it in a loop of some kind. If you return list(zipped) it seems to work in the code challenge. However, I'm not sure why it worked for you in the terminal using print(). I can't seem to get it to work that way, it just returns the memory location of "zipped", which is what you'd expect with a generator.

csj
csj
12,678 Points

It works in Python2:

$ python zippy.py 
[(1, 'a'), (2, 'b'), (3, 'c')]

But not in Python 3: 

python zippy.py 
<zip object at 0x102073248>

And yeah, the documentation is also different. I didn't realize I was reading the Python 2 documentation.

Ryan S
Ryan S
27,276 Points
Ryan S
Ryan S
27,276 Points

Ah that makes sense!

Alexander Davison
Alexander Davison
65,469 Points
Alexander Davison
Alexander Davison
65,469 Points

The problem is that you are printing the zipped variable, and not returning it.

Try returning zipped instead of printing it :)

Good luck! ~alex

csj
csj
12,678 Points

Yeah, true I printed it to the screen in the script I ran in the Terminal so that I could see and verify the correct output. But If you look at the zippy.py (the last code) imported from Workspaces. I return zipped.

def combo(x, y):
    zipped = zip(x, y)
    return zipped
Alexander Davison
Alexander Davison
65,469 Points

Oooooh.. Didn't see that :)

Alexander Davison
Alexander Davison
65,469 Points

What's the error?

csj
csj
12,678 Points
csj
csj
12,678 Points

Uhm, something like. Bummer :D

Alexander Davison
Alexander Davison
65,469 Points

That's all it says?