send probe requests in the air

Code:
#!/usr/bin/env python
#RUN WITH python sendprobereq.py

import os
import random
from scapy.all import *

conf.verb=0 # no verbose

def check_wireless_interfaces():
        chk_wl_int=os.popen("ifconfig | sed 's/[ \t].*//;/^\(lo\|\)$/d;/eth/d' | grep wlan").read() #Check if wlan interfaces are activated
        if not chk_wl_int:
                print ("[+] No wireless interface available. You must turn on a wireless interface.")
                print ("[+] Closing")
                exit()
        else:
                print ("[+] Wireless interface detected")

def check_monitor():
        chk_mon=os.popen("ifconfig | sed 's/[ \t].*//;/^\(lo\|\)$/d;/eth/d' | grep mon").read() #Check if monitor mode has been enabled
        if not chk_mon:
                print ("[+] No monitoring interface detected")
                print ("[+] Available wireless interface(s)\n")
                wl_int_list=os.popen("ifconfig | sed 's/[ \t].*//;/^\(lo\|\)$/d;/eth/d' | grep wlan").read() #Listing wlan interfaces
                print wl_int_list
                int_mon=raw_input("[+] Which interface do you want to monitor?: ")
                while (int_mon != "wlan0") and (int_mon != "wlan1") and (int_mon != "wlan2") and (int_mon != "wlan3"):
                        int_mon=raw_input("[+] Choose an interface from the list: ")
                print ("[+] Trying to enable monitoring on interface "+int_mon)
                os.system("airmon-ng start "+int_mon+" > /dev/null 2>&1") #Activate monitoring on choosen interface
                chk_mon=os.popen("ifconfig | sed 's/[ \t].*//;/^\(lo\|\)$/d;/eth/d' | grep mon").read() #Checking again if monitor mode is enabled
                if not chk_mon:
                        print ("[+] Monitoring couldn't be enabled on interface "+int_mon)
                        print ("[+] Closing")
                else:
                        print ("[+] Monitoring enabled on interface "+int_mon)
        else:
                print ("[+] Monitoring interface detected")

def send_probe():
        i=0

        ssid=raw_input("SSID that will be sent: ")

        while 1:
                try:
                        sendp(RadioTap()/Dot11(type=0,subtype=4,addr1="ff:ff:ff:ff:ff:ff", addr2=RandMAC(),addr3="ff:ff:ff:ff:ff:ff")/Dot11Elt(ID=0,info=ssid)/Dot11Elt(ID=1,info="\x82\x84\x8b\x96"), iface='mon0')
                        i+=1
                except KeyboardInterrupt:
                        print 'packets sent:',i

print ("[+] Checking wireless interfaces")
check_wireless_interfaces()
print ("[+] Checking monitoring interface")
check_monitor()
print ("[+] Start sending - CTRL + C to stop")
send_probe()