#!/usr/bin/python

# custom_dialect.py

import csv

csv.register_dialect("hashes", delimiter="#")

f = open('items3.csv', 'w')

with f:

    writer = csv.writer(f, dialect="hashes")
    writer.writerow(("pencils", 2)) 
    writer.writerow(("plates", 1))
    writer.writerow(("books", 4))

[(7, 'csv.register_dialect', 'csv.register_dialect', False, 'import csv\n'), (13, 'csv.writer', 'csv.writer', False, 'import csv\n')]