test_for_connectivity.py

from ibapi.client import EClient
from ibapi.wrapper import EWrapper  

class IBapi(EWrapper, EClient):
     def __init__(self):
         EClient.__init__(self, self) 

app = IBapi()
app.connect('127.0.0.1', 7497, 123)
app.run()

'''
#Uncomment this section if unable to connect
#and to prevent errors on a reconnect

import time
time.sleep(2)
app.disconnect()
'''