Threading problem

import socket,thread

def scan_port(ip,port,s):
    global openports,t_number,t_lock,open_lock
    if not s.connect_ex((ip, n)):
        open_lock.acquire()
        openports.append(n)
        open_lock.release()
    t_lock.acquire()
    thread_number -= 1
    t_lock.release()
    
ip = '127.0.0.1'
Sport = input("Please enter the start port number: ")
Eport = input("Please enter the end port number: ")
Eport = Eport + 1

print "You are scanning", ip
print "for ports", Sport,"to", Eport - 1

openports = []
sockets = [socket.socket(socket.AF_INET,socket.SOCK_STREAM) for i in range(Sport,Eport)]
open_lock = thread.allocate_lock()
t_number = Eport - Sport + 1
t_lock = thread.allocate_lock()
for n in range(Sport, Eport):
    thread.start_new_thread(scan_port,(ip,n,sockets[n-Sport]))
while t_number > 0: pass
if len(openports) > 0: print "Open ports: ",openports
else: print "No open ports. Sorry."
for s in sockets:
    s.close()