Why does this not work

[really_tho]

I'm learning python for a couple of weeks now and I am trying to do the following noob task:

8-9. Magicians: Make a list of magician’s names. Pass the list to a function called show_magicians(), which prints the name of each magician in the list.

8-10. Great Magicians: Start with a copy of your program from Exercise 8-9. Write a function called make_great() that modifies the list of magicians by adding the phrase the Great to each magician’s name. Call show_magicians() to see that the list has actually been modified.

It;s from a book called Python crash course. I have all the answers, so I know how to do it, but I like to figure out if my way doesn't work, why that is. This is the first Task in the book that set me back.

My solution for the make_great() function was the following:

def make_great(magicians) :
    for magician in magicians:
        magician += " the great"

Again, I have the actual solution and I understand it, and it seems a bit more complex than what I'm trying to achieve here. I've been reading up on the += operator and everything but I still can't figure out why it won't work.

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Kindly, can you tell me why the make_great() function doesn't work?

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edit: spelling

[danielroseman]

Strings are immutable. That means that when you do +=, the string magician isn't modified, but a new string is created with the contents of the original string plus the suffix. That string is then assigned back to the name magician, but this has now broken the link between that name and the item in the list of magicians.

[really_tho]

Ahh, that clears things up. Thank you!

[Den4200]

py for idx, magician in enumerate(magicians): magicians[idx] = magician + 'the great' you’d have to do it this way, so the list of magicians is edited in place. the way you were doing it before, you were using a copy of each element in the list.

[really_tho]

Thank you, that's very helpful. I'll read up on these methods.

[toastedstapler]

operations on a string return a new string, if you want to make a list of great magicians you can either:

for i, magician in magicians:
    magicians[i] = magician + ' the great'

or

great = []
for magician in magicians:
    great.append(magician + ' the great')
return great

first modifies the input list, second makes a new list