Why does my python code seem to be randomnly selecting words? - python-3.x

Question

Hi its my first week learning python and I am making a hangman game
I opened a list of words from a .txt file and then going through the words to remove any words that are shorter than 4 or longer than 7 to make an easy list or words.
When i run the code it removes some of the words but not all of them. I don't understand why and can't seem to figure it out.
Here is the code:
easy_hangman_words = hangman_words("easyhangman.txt")
for x in easy_hangman_words:
print(" {} length {} ".format(x, len(x)))
for word in easy_hangman_words:
if len(word) < 4 or len(word) > 7:
print(word)
easy_hangman_words.remove(word)
I checked the length of each word before if statement and here is a sample:
represent length 9,
Republican length 10,
require length 7 ,
research length 8 ,
resource length 8 ,
respond length 7 ,
response length 8 ,
responsibility length 14 ,
rest length 4 ,
result length 6 ,
return length 6 ,
reveal length 6 ,
rich length 4 ,
right length 5 ,
rise length 4 ,
risk length 4 ,
road length 4 ,
rock length 4 ,
role length 4 ,
room length 4 ,
rule length 4 ,
run length 3 ,
safe length 4 ,
same length 4 ,
save length 4 ,
say length 3 ,
then printed the words in the if loop and here is what i got
represent
research
response
run
say
it seems to have missed Republican, responsibility, and resource.
Any ideas?

Answer 1

You're both reading (in the for loop) and modifying (the remove) the list! This can cause python's for loops to get pretty wonky. There are more pythonic ways to do this, but this should fix the traversal problem.
You should try something like this:
remove_words = []
for word in easy_hangman_words:
if len(word) < 4 or len(word) > 7:
print(word)
remove_words.append(word)
for remove in remove_words:
easy_hangman_words.remove(word)