How do I write to a .csv file with python -

i writing simple script python3.6 , using csv module create csv file. code attached below, , carbon copy of multiple examples have found online, when run code, error message typeerror: bytes-like object required, not 'str'.

import csv file_name = test.csv open(file_name, 'wb') csvfile:    filewriter = csv.writer(csvfile,delimiter=',')    filewriter = writerow(['paul','mary']) 

if don't need binary mode, can use :

with open(file_name, 'w') csvfile:    filewriter = csv.writer(csvfile,delimiter=',')    filewriter.writerow(['paul','mary']) 

check table here see details different modes available.