def METHOD_NAME(self, request, *args, **kwargs):
    if not request.client_id:
        return False
    client_obj = self._get_client(request.client_id)
    if not client_obj:
        return False
    elif 'client_secret' not in request.body:
        return False
    elif client_obj.client_secret != request.body['client_secret']:
        return False
    request.client = client_obj
    return True