Same code producing distinct results in Codeenvy and Windows 8.1

Question

I had made the following code in codevy.io and Python installed in codenvy is 3.5.1. I took this code and put to run in windows 8 with python 3.6.1.

The purpose of the code is to clean some CSV files and write them concatenated into a single CSV file.In codenvy is working, but when running the code in windows the exit file gets blank lines between each Row, I want to know how to get around this:

import csv
import sys
import os
import glob

interesting_files = glob.glob("Vendas_artigos*")

with open('SaidaVendasArtigos.csv','wt',encoding='utf-8-sig') as fout:
    for filename in sorted(interesting_files):
        with open(filename,'rt',encoding='utf-8-sig') as fin:
            next(fin)
            reader = csv.reader(fin)
            writer = csv.writer(fout)
            for row in reader:
                if row:
                    row.pop(0)
                writer.writerow(row)

Python 3.5.1 in Codenvy:

row
row
row

Python 3.6.1 on Windows 8:

row

row

row

Answer 1

I may be wrong, but it may be the moment you use writerow the variable row already have line break, so could use .strip thus:

reader = csv.reader(fin)
writer = csv.writer(fout)
for row in reader:
    if row:
        row.pop(0)
    writer.writerow(row.strip('\r\n'))

In the argument of strip, used \r and \n to remove only line breaks (line feed (LF)) and Carriage Return (CR)

Something that made me curious was the use of row.pop(0), I believe this will always remove the first item of the index, affecting the behavior of for which seems to cause a lot of confusion in the for even, I myself did not understand the need to manipulate the vector if you are just copied the data to a new file, I think maybe you wanted to do something like this:

for row in reader:
    if row:
        writer.writerow(row)

Or:

for row in reader:
    if row:
        writer.writerow(row.strip('\r\n'))

And the reader if you really want to "manipulate" for later use, you could manipulate with pop before or after another for