Python/strings/is_polish_national_id.py
Marek Mazij 9de1c49fe1
feat: Polish ID (PESEL) checker added (#10618)
* feat: Polish ID (PESEL) checker added

* refactor: 'sum' variable renamed to 'subtotal'

* style: typos

* Apply suggestions from code review

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: Christian Clauss <cclauss@me.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
2023-10-17 20:24:16 +02:00

93 lines
2.5 KiB
Python

def is_polish_national_id(input_str: str) -> bool:
"""
Verification of the correctness of the PESEL number.
www-gov-pl.translate.goog/web/gov/czym-jest-numer-pesel?_x_tr_sl=auto&_x_tr_tl=en
PESEL can start with 0, that's why we take str as input,
but convert it to int for some calculations.
>>> is_polish_national_id(123)
Traceback (most recent call last):
...
ValueError: Expected str as input, found <class 'int'>
>>> is_polish_national_id("abc")
Traceback (most recent call last):
...
ValueError: Expected number as input
>>> is_polish_national_id("02070803628") # correct PESEL
True
>>> is_polish_national_id("02150803629") # wrong month
False
>>> is_polish_national_id("02075503622") # wrong day
False
>>> is_polish_national_id("-99012212349") # wrong range
False
>>> is_polish_national_id("990122123499999") # wrong range
False
>>> is_polish_national_id("02070803621") # wrong checksum
False
"""
# check for invalid input type
if not isinstance(input_str, str):
msg = f"Expected str as input, found {type(input_str)}"
raise ValueError(msg)
# check if input can be converted to int
try:
input_int = int(input_str)
except ValueError:
msg = "Expected number as input"
raise ValueError(msg)
# check number range
if not 10100000 <= input_int <= 99923199999:
return False
# check month correctness
month = int(input_str[2:4])
if (
month not in range(1, 13) # year 1900-1999
and month not in range(21, 33) # 2000-2099
and month not in range(41, 53) # 2100-2199
and month not in range(61, 73) # 2200-2299
and month not in range(81, 93) # 1800-1899
):
return False
# check day correctness
day = int(input_str[4:6])
if day not in range(1, 32):
return False
# check the checksum
multipliers = [1, 3, 7, 9, 1, 3, 7, 9, 1, 3]
subtotal = 0
digits_to_check = str(input_str)[:-1] # cut off the checksum
for index, digit in enumerate(digits_to_check):
# Multiply corresponding digits and multipliers.
# In case of a double-digit result, add only the last digit.
subtotal += (int(digit) * multipliers[index]) % 10
checksum = 10 - subtotal % 10
return checksum == input_int % 10
if __name__ == "__main__":
from doctest import testmod
testmod()