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I have to write in Python that performs the following tasks:

1- Download the Movielens datasets from the url ‘http://files.grouplens.org/datasets/movielens/ml- 25m.zip’
2- Download the Movielens checksum from the url ‘http://files.grouplens.org/datasets/movielens/ml- 25m.zip.md5’
3- Check whether the checksum of the archive corresponds to the downloaded one
4- In case of positive check, print the names of the files contained by the downloaded archive

This is what I wrote up to now:

 from zipfile import ZipFile from urllib import request import hashlib def md5(fname): hash_md5 = hashlib.md5() with open(fname, "rb") as f: for chunk in iter(lambda: f.read(4096), b""): hash_md5.update(chunk) return hash_md5.hexdigest() url_datasets = 'http://files.grouplens.org/datasets/movielens/ml-25m.zip' datasets = 'datasets.zip' url_checksum = 'http://files.grouplens.org/datasets/movielens/ml-25m.zip.md5' request.urlretrieve( url_datasets, datasets) request.urlretrieve (url_checksum, checksum) checksum = 'datasets.zip.md5' with ZipFile(datasets, 'r') as zipObj: listOfiles = zipObj.namelist() for elem in listOfiles: print(elem)

So what I'm missing is a way to compare the checksum I computed with the one I downloaded and maybe I can create a function "printFiles" that checks the checksum and in the positive case prints the list of files.

Is there something else I can improve?

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Your code isn't actually making any of the requests.

from zipfile import ZipFile import hashlib import requests def md5(fname): hash_md5 = hashlib.md5() hash_md5.update( open(fname,'rb').read() ) return hash_md5.hexdigest() url_datasets = 'http://files.grouplens.org/datasets/movielens/ml-25m.zip' datasets = 'datasets.zip' url_checksum = 'http://files.grouplens.org/datasets/movielens/ml-25m.zip.md5' checksum = 'datasets.zip.md5' ds = requests.get( url_datasets, allow_redirects=True) cs = requests.get( url_checksum, allow_redirects=True) open( datasets, 'wb').write( ds.content ) ds_md5 = md5(datasets) cs_md5 = cs.content.decode('utf-8').split()[0] print( ds_md5 ) print( cs_md5 ) if ds_md5 == cs_md5: print( "MATCH" ) with ZipFile(datasets, 'r') as zipObj: listOfiles = zipObj.namelist() for elem in listOfiles: print(elem) else: print( "Checksum fail" )
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8 Comments

I don't understand what you mean that my code isn't actually making any of the requests. I ran my code and I get the same checksum I get from yours
Your code didn't make any HTTP requests. You never fetched the files. You imported urllib.request, but you never called it. If you actually have the file, then it was either left over from before, or there is code you didn't show us.
You're right. I don't know why, but I didn't copy that part in my question. I have updated my code
OK. And did you see how I did the comparison in my code? The md5 value you get from the web site has the file name tacked on. You'll have to remove that to do the comparison.
You're making this way too complicated. All you have here are two strings to compare. It's an easy problem. Why are you opposed to the split? I suppose you could use if cs_md5.startswith(ds_md5), but I don't think you've gained anything.
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