send paramiko logs to a logfile,
    if they're not already going somewhere

def log_to_file(filename, level=DEBUG):
    """send paramiko logs to a logfile,
    if they're not already going somewhere"""
    logger = logging.getLogger("paramiko")
    if len(logger.handlers) > 0:
        return
    logger.setLevel(level)
    f = open(filename, "a")
    handler = logging.StreamHandler(f)
    frm = "%(levelname)-.3s [%(asctime)s.%(msecs)03d] thr=%(_threadid)-3d"
    frm += " %(name)s: %(message)s"
    handler.setFormatter(logging.Formatter(frm, "%Y%m%d-%H:%M:%S"))
    logger.addHandler(handler)