@staticmethod
def split(business_id):
    """
        Split a company id to a id number part and a checksum digit.

        @param business_id: a valid finnish business id.
        """
    val = str(business_id)
    if len(val) == 0:
        return '', ''
    parts = val.split('-')
    if len(parts) == 1:
        return parts[0][:-1], parts[0][-1]
    else:
        return parts[0], parts[1]
