IBAN check in python

iban.py

import re
 
_country2length = dict(
    AL=28, AD=24, AT=20, AZ=28, BH=22, BY=28, BE=16,
    BA=20, BR=29, BG=22, CR=22, HR=21, CY=28, CZ=24,
    DK=18, DO=28, EG=29, SV=28, EE=20, FO=18, FI=18,
    FR=27, GE=22, DE=22, GI=23, GR=27, GL=18, GT=28,
    VA=22, HU=28, IS=26, IQ=23, IE=22, IL=23, IT=27,
    JO=30, KZ=20, XK=20, KW=30, LV=21, LB=28, LY=25,
    LI=21, LT=20, LU=20, MT=31, MR=27, MU=30, MD=24,
    MC=27, ME=22, NL=18, MK=19, NO=15, PK=24, PS=29,
    PL=28, PT=25, QA=29, RO=24, LC=32, SM=27, ST=25,
    SA=24, RS=22, SC=31, SK=24, SI=19, ES=24, SD=18,
    SE=24, CH=21, TL=23, TN=24, TR=26, UA=29, AE=23,
    GB=22, VG=24)
 
def valid_iban(iban):
    # Ensure upper alphanumeric input.
    iban = iban.replace(' ','').replace('\t','')
    if not re.match(r'^[\dA-Z]+$', iban): 
        return False
    # Validate country code against expected length.
    if len(iban) != _country2length[iban[:2]]:
        return False
    # Shift and convert.
    iban = iban[4:] + iban[:4]
    digits = int(''.join(str(int(ch, 36)) for ch in iban)) #BASE 36: 0..9,A..Z -> 0..35
    return digits % 97 == 1
 
if __name__ == '__main__':
    for account in ["GB82 WEST 1234 5698 7654 32", "GB82 TEST 1234 5698 7654 32"]:
        print('%s validation is: %s' % (account, valid_iban(account)))

Updated IBAN lenght list (https://www.iban.com/structure):

IBAN_LEN_COUNTRY = dict(
    AL=28, AD=24, AT=20, AZ=28, BH=22, BY=28, BE=16,
    BA=20, BR=29, BG=22, CR=22, HR=21, CY=28, CZ=24,
    DK=18, DO=28, EG=29, SV=28, EE=20, FO=18, FI=18,
    FR=27, GE=22, DE=22, GI=23, GR=27, GL=18, GT=28,
    VA=22, HU=28, IS=26, IQ=23, IE=22, IL=23, IT=27,
    JO=30, KZ=20, XK=20, KW=30, LV=21, LB=28, LY=25,
    LI=21, LT=20, LU=20, MT=31, MR=27, MU=30, MD=24,
    MC=27, ME=22, NL=18, MK=19, NO=15, PK=24, PS=29,
    PL=28, PT=25, QA=29, RO=24, LC=32, SM=27, ST=25,
    SA=24, RS=22, SC=31, SK=24, SI=19, ES=24, SD=18,
    SE=24, CH=21, TL=23, TN=24, TR=26, UA=29, AE=23,
    GB=22, VG=24)

Also, to avoid missing key errors
line 19: if iban[:2] not in _country2length.keys() or len(iban) != _country2length[iban[:2]]:

Updated dict. Thank you!