csv.Error: iterator should return strings, not bytes

You open the file in text mode.

More specifically:

ifile  = open('sample.csv', "rt", encoding=<theencodingofthefile>)

Good guesses for encoding is "ascii" and "utf8". You can also leave the encoding off, and it will use the system default encoding, which tends to be UTF8, but may be something else.

In Python3, csv.reader expects, that passed iterable returns strings, not bytes. Here is one more solution to this problem, that uses codecs module:

import csv
import codecs
ifile  = open('sample.csv', "rb")
read = csv.reader(codecs.iterdecode(ifile, 'utf-8'))
for row in read :
    print (row) 

The reason it is throwing that exception is because you have the argument rb, which opens the file in binary mode. Change that to r, which will by default open the file in text mode.

Your code:

import csv
ifile  = open('sample.csv', "rb")
read = csv.reader(ifile)
for row in read :
    print (row) 

New code:

import csv
ifile  = open('sample.csv', "r")
read = csv.reader(ifile)
for row in read :
    print (row)