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Python Python Collections (2016, retired 2019) Lists Disemvowel

Code Challenge 1 in Python Collections - Why doesn't this work??

I understand how to get around this for the challenge (create a new word and append to it), but I don't understand why this code isn't working?? I created a script on my macbook and I am trying to run it there. (my laptop runs 2.7, hence the raw_input function, but everything else seems to work the same as treehouse). This is the full script:

def disemvowel(word):

    lword = list(word)


    for letter in lword:

        print("letter is: " + letter)

        if letter.lower() in ("a", "e", "i", "o", "u"):


    return str(lword)

word = raw_input("Word: ")

new_word = disemvowel(word)


When I run this code, I get the following output:

 Aniel:TeamTreehouse Anne$ python disemvowel.py
 Word: treehouse
 ['t', 'r', 'e', 'e', 'h', 'o', 'u', 's', 'e']
 letter is: t
 letter is: r
 letter is: e
 letter is: h
 letter is: o
 letter is: s
 letter is: e
 ['t', 'r', 'h', 'u', 's', 'e']

Why is it acting so weird? I can't figure out why it's skipping letters and ignoring the last letter even though it hits?

It is not safe to remove elements from list during iteration:

for letter in lword:

That actually makes a lot of sense. I wouldn't free a node in a linked list in C while i was still pointing to that node in an iteration for the same reason. Thanks for the help!