def update_alias(self):
        """Update lambda alias to point to $LATEST."""
        LOG.info('Updating alias %s to point to $LATEST', self.env)

        try:
            self.lambda_client.update_alias(FunctionName=self.app_name, Name=self.env, FunctionVersion='$LATEST')
        except boto3.exceptions.botocore.exceptions.ClientError as error:
            LOG.debug('Update alias error: %s', error)
            LOG.info("Alias update failed. Retrying...")
            raise
Update lambda alias to point to $LATEST.