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
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
|
# ssn.py - functions for handling SSNs
#
# Copyright (C) 2011, 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
"""SSN (U.S. Social Security Number).
The Social Security Number is used to identify individuals for taxation
purposes.
>>> is_valid('111-22-3333')
True
>>> is_valid('1112-23333')
False
>>> is_valid('666-00-0000')
False
>>> compact('1234-56-789')
'123456789'
>>> format('111223333')
'111-22-3333'
"""
import re
from stdnum.util import clean
# regular expression for matching SSN
_ssn_re = re.compile('^(?P<area>[0-9]{3})-?(?P<group>[0-9]{2})-?(?P<serial>[0-9]{4})$')
# blacklist of SSNs
_ssn_blacklist = set(('078-05-1120', '457-55-5462', '219-09-9999'))
def compact(number):
"""Convert the number to the minimal representation. This strips the
number of any valid separators and removes surrounding whitespace."""
return clean(number, '-').strip()
def is_valid(number):
"""Checks to see if the number provided is a valid SSN. This checks
the length, groups and formatting if it is present."""
try:
match = _ssn_re.search(number.strip())
except:
return False
if not match:
return False
area = match.group('area')
group = match.group('group')
serial = match.group('serial')
# check for all-0 or some unused areas
# (9xx also won't be issued which includes the advertising range)
if area == '000' or area == '666' or area[0] == '9' or \
group == '00' or serial == '0000':
return False
# check blacklists
return format(number) not in _ssn_blacklist
def format(number):
"""Reformat the passed number to the standard format."""
if len(number) == 9:
number = number[:3] + '-' + number[3:5] + '-' + number[5:]
return number
|