<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def _driver_signing_reg_reverse_conversion(cls, val, **kwargs):
        '''
        converts the string value seen in the GUI to the correct registry value
        for secedit
        '''
        if val is not None:
            if val.upper() == 'SILENTLY SUCCEED':
                return ','.join(['3', '0'])
            elif val.upper() == 'WARN BUT ALLOW INSTALLATION':
                return ','.join(['3', chr(1)])
            elif val.upper() == 'DO NOT ALLOW INSTALLATION':
                return ','.join(['3', chr(2)])
            else:
                return 'Invalid Value'
        else:
            return 'Not Defined'