1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
# nif.py - functions for handling Portuguese VAT numbers
# coding: utf-8
#
# Copyright (C) 2012 Arthur de Jong
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301 USA
"""NIF (Número de identificação fiscal, Portuguese VAT number).
The NIF (Número de identificação fiscal, NIPC, Número de Identificação de
Pessoa Colectiva) is used for VAT purposes. It is a 9-digit number with a
simple checksum.
>>> compact('PT 501 964 843')
'501964843'
>>> is_valid('PT 501 964 843')
True
>>> is_valid('PT 501 964 842') # invalid check digits
False
"""
from stdnum.util import clean
def compact(number):
"""Convert the number to the minimal representation. This strips the
number of any valid separators and removes surrounding whitespace."""
number = clean(number, ' -.').upper().strip()
if number.startswith('PT'):
number = number[2:]
return number
def calc_check_digit(number):
"""Calculate the check digit. The number passed should not have the
check digit included."""
return str((11 - sum((9 - i) * int(n) for i, n in enumerate(number)) ) % 11 % 10)
def is_valid(number):
"""Checks to see if the number provided is a valid VAT number. This
checks the length, formatting and check digit."""
try:
number = compact(number)
except:
return False
return number.isdigit() and len(number) == 9 and \
number[0] != '0' and calc_check_digit(number[:-1]) == number[-1]
|