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
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
|
# pan.py - functions for handling Indian Permanent Account number (PAN)
#
# Copyright (C) 2017 Srikanth Lakshmanan
#
# 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
"""PAN (Permanent Account Number, Indian income tax identifier).
The Permanent Account Number (PAN) is a 10 digit alphanumeric identifier for
Indian individuals, families and corporates for income tax purposes.
The number is built up of 5 characters, 4 numbers and 1 character. The fourth
character indicates the type of holder of the number and the last character
is computed by an undocumented checksum algorithm.
More information:
* https://en.wikipedia.org/wiki/Permanent_account_number
>>> validate('ACUPA7085R')
'ACUPA7085R'
>>> validate('234123412347')
Traceback (most recent call last):
...
InvalidLength: ...
>>> validate('ABMPA32111') # check digit should be a letter
Traceback (most recent call last):
...
InvalidFormat: ...
>>> validate('ABMXA3211G') # invalid type of holder
Traceback (most recent call last):
...
InvalidComponent: ...
>>> mask('AAPPV8261K')
'AAPPVXXXXK'
>>> info('AAPPV8261K')['card_holder_type']
'Individual'
"""
import re
from stdnum.exceptions import *
from stdnum.util import clean
_pan_re = re.compile(r'^[A-Z]{3}[ABCFGHLJPTK][A-Z]\d{4}[A-Z]$')
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, ' -').upper().strip()
def validate(number):
"""Check if the number provided is a valid PAN. This checks the
length and formatting."""
number = compact(number)
if len(number) != 10:
raise InvalidLength()
if not (number[:5].isalpha() and number[5:-1].isdigit() and
number[-1].isalpha()):
raise InvalidFormat()
info(number) # used to check 4th digit
return number
def is_valid(number):
"""Check if the number provided is a valid PAN. This checks the
length and formatting."""
try:
return bool(validate(number))
except ValidationError:
return False
_card_holder_types = {
'A': 'Association of Persons (AOP)',
'B': 'Body of Individuals (BOI)',
'C': 'Company',
'F': 'Firm',
'G': 'Government',
'H': 'HUF (Hindu Undivided Family)',
'L': 'Local Authority',
'J': 'Artificial Juridical Person',
'P': 'Individual',
'T': 'Trust (AOP)',
'K': 'Krish (Trust Krish)',
}
def info(number):
"""Provide information that can be decoded from the PAN."""
number = compact(number)
card_holder_type = _card_holder_types.get(number[3])
if not card_holder_type:
raise InvalidComponent()
return {
'card_holder_type': card_holder_type,
'initial': number[4],
}
def mask(number):
"""Mask the PAN as per CBDT masking standard."""
number = compact(number)
return number[:5] + 'XXXX' + number[-1:]
|