NUMBERS_PLUS_LETTER = "Input must be a string of 8 numbers plus letter"
LOOKUP_LETTERS = "TRWAGMYFPDXBNJZSQVHLCKE"
def is_spain_national_id(spanish_id: str) -> bool:
"""
Spain National Id is a string composed by 8 numbers plus a letter
The letter in fact is not part of the ID, it acts as a validator,
checking you didn't do a mistake when entering it on a system or
are giving a fake one.
https://en.wikipedia.org/wiki/Documento_Nacional_de_Identidad_(Spain)#Number
>>> is_spain_national_id("12345678Z")
True
>>> is_spain_national_id("12345678z") # It is case-insensitive
True
>>> is_spain_national_id("12345678x")
False
>>> is_spain_national_id("12345678I")
False
>>> is_spain_national_id("12345678-Z") # Some systems add a dash
True
>>> is_spain_national_id("12345678")
Traceback (most recent call last):
...
ValueError: Input must be a string of 8 numbers plus letter
>>> is_spain_national_id("123456709")
Traceback (most recent call last):
...
ValueError: Input must be a string of 8 numbers plus letter
>>> is_spain_national_id("1234567--Z")
Traceback (most recent call last):
...
ValueError: Input must be a string of 8 numbers plus letter
>>> is_spain_national_id("1234Z")
Traceback (most recent call last):
...
ValueError: Input must be a string of 8 numbers plus letter
>>> is_spain_national_id("1234ZzZZ")
Traceback (most recent call last):
...
ValueError: Input must be a string of 8 numbers plus letter
>>> is_spain_national_id(12345678)
Traceback (most recent call last):
...
TypeError: Expected string as input, found int
"""
if not isinstance(spanish_id, str):
raise TypeError(f"Expected string as input, found {type(spanish_id).__name__}")
spanish_id_clean = spanish_id.replace("-", "").upper()
if len(spanish_id_clean) != 9:
raise ValueError(NUMBERS_PLUS_LETTER)
try:
number = int(spanish_id_clean[0:8])
letter = spanish_id_clean[8]
except ValueError as ex:
raise ValueError(NUMBERS_PLUS_LETTER) from ex
if letter.isdigit():
raise ValueError(NUMBERS_PLUS_LETTER)
return letter == LOOKUP_LETTERS[number % 23]
if __name__ == "__main__":
import doctest
doctest.testmod()