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Python Python Collections (2016, retired 2019) Slices Back and Forth

Posted by akshaan Mazumdar
akshaan Mazumdar
997 Points

Not working , Why?

not changing favorite things but getting error that i am

slices.py 
favorite_things = ['raindrops on roses', 'whiskers on kittens', 'bright copper kettles',
                   'warm woolen mittens', 'bright paper packages tied up with string',
                   'cream colored ponies', 'crisp apple strudels']
slice1 = favorite_things[1:4]
slice2 = favorite_things[5 : ]

sorted_things = favorite_things
sorted_things = sorted_things.sort()

1 Answer

Jennifer Nordell
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STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there! You're doing really well, but the problem here is that you haven't assigned a copy of the favorite_things list to sorted_things but rather a reference to the original list. This means that you are, in fact, changing the original `favorite_things' list. I whipped up a simple demonstration of the difference in a Python workspace and hopefully it will clearly demonstrate the difference between storing a copy of a list and a reference to a list.

fruits1 = ['apple', 'grape', 'banana']

fruits2 = fruits1
print("The original fruits list:")
print(fruits1)
fruits2.append('kiwi')

print("The original fruits list after appending to fruits2:")
print(fruits1)
print("Fruits 2 list:")
print(fruits2)


fruits3 = fruits1[:]
fruits3.append('orange')

print("The fruits list after appending orange to list 3:")
print(fruits1)
print("The third fruits list: ")
print(fruits3)

I highly recommend running this in a workspace and taking a look at the output. It might not be what you expect :smiley: However, I feel confident that you can complete the challenge once you see how this works! But if you're still stuck, let me know! :sparkles:

edited for additional information

In the first part, I assign a reference to the fruits1 list to fruits2. In the second part, I assign a copy of the fruits1 list to fruits3.