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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _raise_on_invalid_client(self, request):
 """Raise on failed client authentication."""

        if self.request_validator.client_authentication_required(request):
            if not self.request_validator.authenticate_client(request):
                log.debug('Client authentication failed, %r.', request)
                raise InvalidClientError(request=request)
        elif not self.request_validator.authenticate_client_id(request.client_id, request):
            log.debug('Client authentication failed, %r.', request)
            raise InvalidClientError(request=request)