Create a 4-digit hash code for each guest loaded from a CSV file

guest_hash_generator.py

import csv
import base64
import hashlib

f = open('guests.csv', "r", encoding='utf-8', errors='ignore')
csv_f = csv.reader(f)
for row in csv_f:
    s = ''
    for element in row:
        s += element
coded_s = s.encode(encoding='utf-8')
mrHash = hashlib.sha1(coded_s)
code = base64.urlsafe_b64encode(mrHash.digest()[0:3])
final_code = code.decode('utf-8')
final_code = final_code.replace('_', 'x')
final_code = final_code.replace('-', 'z')
print(final_code.upper())