def calculate_checksum(number: str) -> str:
            """Calculate the checksum using mod 11,2 method"""
            factors = [7, 9, 10, 5, 8, 4, 2]
            sum_ = 0
            for x, y in zip(number, factors):
                sum_ = sum_ + int(x) * y
            if sum_ % 11 == 1:
                raise ValueError("Checksum 1 is invalid")
            if sum_ % 11 == 0:
                return "0"
            else:
                return str(11 - sum_ % 11)
Calculate the checksum using mod 11,2 method
faker/providers/company/fi_FI/__init__.py