Question

So I’m writing a python script that will clean file names of useless and unwanted characters, but I’m running into a problem, I can’t seem to figure out how to return a list or dictionary with all of the items in it that I iterated over. it only returns the first item I iterated over. this is my first time writing in python. any help would be greatly appreciated. I’m mostly writing this to learn. the clean_title() method is the one I’m trying to return from. and I call it at the bottom.

import os
import re

# here is how all my video files will look after this
# show name Season 1 Episode 1

filename = os.listdir("E:/Videos/TV/tv-show")



def clean_title(filename):
    name = {}
    for title in filename:
        n_title = title.split('.')
        index = [i for i, item in enumerate(n_title) if re.search('\w\d{2}\w\d{2}', item)]
        if len(index) > 0:
            name = {'title':n_title[0:index[0]], 'ep_info':n_title[index[0]]}
            return name


def get_show_name(filename):
    pass


def update_title():
    #show_title = get_show_name + ' ' + get_episode_info
    #print show_title


if __name__=="__main__":
    test = clean_title(filename)
    print test

Answer 1

You have two distinct problems.

The first is that you’re returning from inside your loop, so you will only have processed a single iteration of the loop when you hit the return statement. That’s why it looks like you’re getting the first iterated value when, in fact, you’re never reaching the other iterations.

You can fix this by out-denting the return statement to the correct level.

The second problem is in the way you’re accruing your results to return from clean_title(). You are only ever storing a single cleaned title in the name variable. Each time through the loop you’re overwriting the previously calculated title with the new one from that iteration. Even if you fix the return issue, the current version would then return the last title you computed.

You can accrue your results in either a list or a dictionary. If a list, you initialize with name = [] and add new titles with name.append(title_goes_here). If you want to accrue your results in a dictionary, you initialize with name = {} and add new titles with name[index_goes_here] = title_goes_here. Note that in the case of a dictionary you need to have some logical key value (usually an integer or string) that you will use to recover the value later on.

Finally, I have to add that I find your use of singular case (filename, title, clean_title) for plural objects and actions to be confusing. I’d call a list of file names filenames, and so on.