Python CNPJ validation

cnpj.py

import re
from typing import Union


class InvalidCNPJ(Exception):
    pass


def clean_cnpj(value: Union[int, str]) -> str:
    """
    Validates and cleans CNPJs, works with both string and ints as inputs

    >>> clean_cnpj("57.823.152/0001-01")
    '57.823.152/0001-01'

    >>> clean_cnpj("32820286000148")
    '32.820.286/0001-48'

    >>> clean_cnpj("04520130000106")
    '04.520.130/0001-06'

    >>> clean_cnpj(4520130000106)
    '04.520.130/0001-06'

    >>> clean_cnpj("32.820.286/0000-67")
    Traceback (most recent call last)
    InvalidCNPJ:
    """
    if isinstance(value, int):
        v = f"{value:014d}"
    elif isinstance(value, str):
        v = re.sub(r"\D", "", value)
    else:
        raise InvalidCNPJ

    if len(v) != 14:
        raise InvalidCNPJ

    # Suffixes start at 0001
    suffix = int(v[8:12])
    if suffix == 0:
        raise InvalidCNPJ

    # CNPJs with the following basic numbers are not valid:
    # 11.111.111, 22.222.222, 33.333.333, 44.444.444, 55.555.555
    # 66.666.666, 77.777.777, 88.888.888, 99.999.999.
    if v[0:8] in {
        "11111111",
        "22222222",
        "33333333",
        "44444444",
        "55555555",
        "66666666",
        "77777777",
        "88888888",
        "99999999",
    }:
        raise InvalidCNPJ

    d = [int(i) for i in v[:14]]

    v1 = 5 * d[0] + 4 * d[1] + 3 * d[2] + 2 * d[3]
    v1 += 9 * d[4] + 8 * d[5] + 7 * d[6] + 6 * d[7]
    v1 += 5 * d[8] + 4 * d[9] + 3 * d[10] + 2 * d[11]
    v1 = 11 - v1 % 11
    if v1 >= 10:
        v1 = 0
    if v1 != d[12]:
        raise InvalidCNPJ

    v2 = 6 * d[0] + 5 * d[1] + 4 * d[2] + 3 * d[3]
    v2 += 2 * d[4] + 9 * d[5] + 8 * d[6] + 7 * d[7]
    v2 += 6 * d[8] + 5 * d[9] + 4 * d[10] + 3 * d[11]
    v2 += 2 * d[12]
    v2 = 11 - v2 % 11
    if v2 >= 10:
        v2 = 0
    if v2 != d[13]:
        raise InvalidCNPJ

    # CNPJ with an suffix number greater than 0300 and with the first three positions
    # of the BASIC number with 000 (zeros) will not be considered valid.
    # Unless the basic number of the CNPJ is equal to 00.000.000, then it's valid.
    if v[0:8] != "00000000" and v[0:3] == "000" and suffix > 300:
        raise InvalidCNPJ

    return f"{v[0:2]}.{v[2:5]}.{v[5:8]}/{v[8:12]}-{v[12:14]}"