Python: If file does not end with , move up the line below - python-3.x

Question

So I have a csv file which is created from a program as a report. This file has lines in it that are not correctly split, all of there lines should end with ,\n What I want to do is if the line does not end with a ,\n the script should move the line from below to the line that is missing , to up
this is how I have tried so far
with open('test.csv', 'r') as data, open('output.csv','w') as output:
for line in data:
if not line.endswith(',\n'):
line = line.rstrip()
output.write(line)`
but this is not working in below case:
name, address, pincode,
amruta, peth, 41578,
ashwini,'peth,
MH', 415407,
akshay, sangli,
478595,
Output should be
name, address, pincode,
amruta, peth, 41578,
ashwini,'peth,MH', 415407,
akshay, sangli, 478595,
Output i am getting
name, address, pincode,
amruta, peth, 41578,
ashwini,'peth,
MH', 415407,
akshay, sangli, 478595,

Answer 1

The problem is that for the lines:
ashwini,'peth,
MH', 415407,
The upper line does, in fact, en with ',', so it does work "as intended".
So, instead, you could work with the column size expected. The following code solves your problem:
with open('test.txt', 'r') as data, open('output.txt','w') as output:
bad_size = False
bad_line = None
for line in data:
columns = line.split(',')
if (len(columns) - 1) < 3:
if bad_size:
line = bad_line.rstrip('\n') + line
bad_size = False
else:
bad_size = True
bad_line = line
if not bad_size:
output.write(line)