def bank_identifier(self):
        """Return the IBAN's Bank Identifier."""
        end = get_iban_spec(self.country_code).bban_split_pos + 4
        return self._id[4:end]
def bank_identifier ( self ) : end = get_iban_spec ( self . country_code ) . bban_split_pos + 4 return self . _id [ 4 : end ]
Return the IBAN's Bank Identifier.