'Get a dictionary of unqualified simple registration
arguments representing this request.
This method is essentially the inverse of
C{L{parseExtensionArgs}}. This method serializes the simple
registration request fields.
@rtype: {str:str}'

def getExtensionArgs(self):

    args = {}
    if self.required:
        args['required'] = ','.join(self.required)
    if self.optional:
        args['optional'] = ','.join(self.optional)
    if self.policy_url:
        args['policy_url'] = self.policy_url
    return args
