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Python Python Collections (2016, retired 2019) Lists Disemvowel

what is wrong with my code?

def disemvowel(word): word_list = list(word) for letter in word_list: if letter in ["A", "a", "E", "e", "I", "i", "O", "o", "U", "u"]: word_list.remove(letter) word_string = ''.join(word_list) return word_string

disemvowel.py
def disemvowel(word):
    word_list = list(word)
    for letter in word_list:
        if letter in ["A", "a", "E", "e", "I", "i", "O", "o", "U", "u"]:
            word_list.remove(letter)
    word_string = ''.join(word_list)
    return word_string

3 Answers

Steven Parker
Steven Parker
229,921 Points

When you alter an iterable while it is being used to control a loop, it can cause items to be skipped over. One way to avoid this is to iterate using a copy of the iterable.

Or you could simply iterate on the original string word instead :wink:

Steven Parker
Steven Parker
229,921 Points

That would work in this case, but it's not a good practice in case the number or order of items got changed in the conversion process.

True.

Thank you Steven and Alexander for your answers! I tried using the original string word, but then I could not use the remove() method in the if statement.

Steven, Could you please explain how to use a copy of the iterable to solve this question?

Steven Parker
Steven Parker
229,921 Points
    for letter in word_list.copy():   # or...
    for letter in word_list[:]:       # an unlimited slice is also a copy

Thank you Steven for your help! Much appreciated!