IP remains unchanged

I am trying to connect to Tor by code and change my identity. The results I have received so far are that I am successfully connecting but cannot change my identity. Here is my code:

import socket
import socks
import httplib

def connectTor():
    socks.setdefaultproxy(socks.PROXY_TYPE_SOCKS5,"127.0.0.1",9150,True)
    socket.socket = socks.socksocket

def newIdentity():
    socks.setdefaultproxy()

    s = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    s.connect(("127.0.0.1",9151))   
    s.send("AUTHENTICATE\r\n")

    response = s.recv(128)

    if response.startswith("250"):
        s.send("SIGNAL NEWNYM\r\n")

    s.close()    
    connectTor()

def showIP():
    conn = httplib.HTTPConnection("my-ip.herokuapp.com")
    conn.request("GET","/")
    response = conn.getresponse()
    print (response.read())

def main():
    connectTor()    
    print("Connected to Tor")    
    showIP()    

    print("Hew Id is")
    newIdentity()
    showIP()

main() 

      

        
        
        
      

    

Any help or advice is greatly appreciated.