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Python

Posted by Nathan McGinley
Nathan McGinley
4,627 Points

Python I/O using random library, keep getting errors trying to use .choice (anyone?)

I've been trying to practice what I learned from the Python course and the Python I/O workshop. I'm trying to take a list of words in a text file and choose 7 random words and add them to another file while checking that file to see if a word has already been added.

import random

words = []
# open up list of words
def new_words(n):
    with open('word_list.txt') as file:
        i = 0
        while i < n:
            rand = random.choice(file.readlines)
            words.append(rand)
            i += 1

def check_duplicates(words):
    with open('added.txt') as file:
        i = 0
        for word in words:
            if word in file.readlines:
                words.remove(word)
                i += 1
        new_words(i)

def add_to_file(words):
    with open('added.txt' 'a') as file:
        file.writelines(words)

new_words(7)
check_duplicates(words)
add_to_file(words)

word_list.txt:

cat
dog
cheddar
love
cheese
usb
paper
table
sleep
tired
lamp
pencil
pen
lead

added.txt:

cat

But I keep getting this error, I don't understand it and have tried searching online and docs to no avail:

Traceback (most recent call last):
  File ".../word_list.py", line 54, in <module>
    new_words(7)
  File ".../word_list.py", line 37, in new_words
    rand = random.choice(file.readlines)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/random.py", line 253, in choice
    i = self._randbelow(len(seq))
TypeError: object of type 'builtin_function_or_method' has no len()

Can anyone explain what I'm doing wrong and what this error is?

Elizabeth Ryan
Elizabeth Ryan
1,151 Points

I am having the same issue. Did you get a solution for this?

Nathan McGinley
Nathan McGinley
4,627 Points

No seems like this question is either under the radar or people aren't interested in answering. Shame :(

1 Answer

Carlos Federico Puebla Larregle
Carlos Federico Puebla Larregle
21,074 Points
Carlos Federico Puebla Larregle
Carlos Federico Puebla Larregle
21,074 Points

Maybe I 'm wrong but I think you have to put a comma between the file and the "mode" inside of the "add_to_file()" function:

def add_to_file(words):
    with open('added.txt', 'a') as file:
        file.writelines(words)
Nathan McGinley
Nathan McGinley
4,627 Points

I added that but makes no difference to the error, good spot though thanks!