Shows stats (possibly limited by hostname)

def action_stats(self, hostname=None):
        "Shows stats (possibly limited by hostname)"
        format = "%-35s %-11s %-11s %-11s %-11s"
        print format % ("HOST", "OPEN", "COMPLETED", "BYTES IN", "BYTES OUT")
        for host, details in sorted(self.client.stats(hostname).items()):
            print format % (
                host,
                details.get("open_requests", 0),
                details.get("completed_requests", 0),
                details.get("bytes_received", 0),
                details.get("bytes_sent", 0),
            )