Stealth Syn Scanner to check open ports

robot.py

#!/usr/bin/python
#Robot.py 
from scapy.all import *
from pyfiglet import Figlet
logo = Figlet(font='graffiti')
print(logo.renderText('%R%\nfs0c131y..%'))
ip = input("Enter the ip address or url:\n")
port = int(input("Enter the port number:\n"))
def checkhost():
    ping = IP(dst=ip)/ICMP()
    res = sr1(ping,timeout=1,verbose=0)
    if res == None:
        print("This host is down")
    else:
        print("This host is up")

#function to check open port
def checkport():
    tcpRequest = IP(dst=ip)/TCP(dport=port,flags="S")
    tcpResponse = sr1(tcpRequest,timeout=1,verbose=0)
    try:
        if tcpResponse.getlayer(TCP).flags == "SA":
            print(port,"is listening")
    except AttributeError:
        print(port,"is not listening")

checkhost()
checkport()