'Constructor.
When called without arguments, create an unconnected instance.
With a hostname argument, it connects the instance; port number
and timeout are optional.'

def __init__(self, host=None, port=0, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):

    self.debuglevel = DEBUGLEVEL
    self.host = host
    self.port = port
    self.timeout = timeout
    self.sock = None
    self.rawq = ''
    self.irawq = 0
    self.cookedq = ''
    self.eof = 0
    self.iacseq = ''
    self.sb = 0
    self.sbdataq = ''
    self.option_callback = None
    if (host is not None):
        self.open(host, port, timeout)
