# stdnum.at.uid

UID (Umsatzsteuer-Identifikationsnummer, Austrian VAT number).

The Austrian UID is a 9-digit number that starts with a U (optionally preceded with AT). The last digit is a check digit.

    >>> validate('AT U13585627')
    'U13585627'
    >>> calc_check_digit('U1358562')
    '7'
    >>> validate('U13585626')  # incorrect check digit
    Traceback (most recent call last):
        ...
    InvalidChecksum: ...

stdnum.at.uid.calc_check_digit(number: str) → str

  Calculate the check digit. The number passed should not have the check digit included.

stdnum.at.uid.compact(number: str) → str

  Convert the number to the minimal representation. This strips the number of any valid separators and removes surrounding whitespace.

stdnum.at.uid.is_valid(number: str) → bool

  Check if the number is a valid VAT number.

stdnum.at.uid.validate(number: str) → str

  Check if the number is a valid VAT number. This checks the length, formatting and check digit.