threads/sockets quick question.

[ed]

this script should create individual threads to scan a range of IP
addresses, but it doesnt, it simple ... does nothing. it doesnt hang
over anything, the thread is not being executed, any ideas anyone?
----------

import socket
import threading
import traceback


MAX_THREADS = 50


class scanThread(threading.Thread):
    def run(self):
        try:
            ss = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            ss.connect((ip, port_counter))
            print "%s | %d OPEN" % (ip, port_counter)
            ss.close()
            print "scanned: ",port_counter,"\n"
        except:
            traceback.print_exc()
# end class -------------------


def scan(ip, begin, end):
        port_counter = 0
	for port_counter in range(begin, end):
            while threading < MAX_THREADS:
                scanThread().start()
# end function -------------------
scan("localhost", 0, 10000)