避免因连接或互联网故障而异常中断脚本

Question

问候，我编写了以下脚本，该脚本通过txt文件为我带来了网络状态。我不知道这是否是最快的方法，但是它对我有用，问题是我不太清楚套接字的异常问题。我正在运行超时，但是当没有互联网或套接字的连接排队时，脚本会不断中断。

# pip install termcolor, pip install urllib3, pip install colorama
import urllib.request
import urllib.error
import time
import os
import ssl
import socket
#import httplib #este es para python2
from termcolor import *
#Para colorear en windows
import colorama
colorama.init()
#Para desastivar el check de SSL
ssl._create_default_https_context = ssl._create_unverified_context

__author__ = "Antonio Orozco R"
__copyright__ = "Copyright (C) 2018 Antonio Orozco R. antoniojorz@hotmail.com"
__license__ = "GPL/GNU V3"
__version__ = "1.1"

#abrir archivo
archivo = open("url.txt", "r")
#Contar numeros de lineas
iterlen = lambda it: sum(1 for _ in it)
cant = iterlen(open("url.txt"))
#ENCABEZADOS DE COLUMNAS
title_Fecha = "Fecha"
title_Url = "URL"
title_Estado = "Estado"
title_Razon = "Razon"
title_Tiempo = "Tiempo"
print ('------------------------------------------------------------------------------------------------------------------------------------------------------')
print ('------------------------------------------------------------------------------------------------------------------------------------------------------')
cprint("Este script esta bajo licencia: "+__license__+" "+__copyright__+" "+__version__,'white')
print ('------------------------------------------------------------------------------------------------------------------------------------------------------')
cprint("%-25s %-80s %-30s %-7s" %(title_Fecha, title_Url, title_Estado, title_Tiempo),'white')
print ('------------------------------------------------------------------------------------------------------------------------------------------------------')

while True:
    cantT=0
    TIMEOUT=8
    for site in archivo.readlines():
        #Borro los saltos de lineas
        if site[-1] == '\n':
            site = site[:-1]
        try:
            #Variables de conexion y estado
            opener = urllib.request.build_opener()
            opener.addheaders = [('User-agent', 'Mozilla/5.0')]
            conn = opener.open(site, timeout=TIMEOUT)
            html_contents = conn.read()
            st = conn.code
            cantT+= 1
            #se calcula el tiempo transcurido para el check
            inicio = time.time()
            elapse_time = str(time.time()-inicio)[0:6]
            if conn.code in (200, 401, 301, 302):
                cprint("%-25s %-80s %-30s %-7s" %(time.strftime("%c"),site, st,elapse_time),'green')
            if conn.code in (408, 501, 503):
                cprint("%-25s %-80s %-30s %-7s" %(time.strftime("%c"),site, st,elapse_time),'yellow')
            #Reload
            if cantT == cant:
                #cierro archivo
                archivo.close()
                #reabro archivo
                archivo = open("url.txt", "r")
                #Contar numeros de lineas
                iterlen = lambda it: sum(1 for _ in it)
                cant = iterlen(open("url.txt"))
                print ('------------------------------------------------------------------------------------------------------------------------------------------------------')
                print ('------------------------------------------------------------------------------------------------------------------------------------------------------')
                cprint("Este script esta bajo licencia: "+__license__+" "+__copyright__+" "+__version__,'white')
                print ('------------------------------------------------------------------------------------------------------------------------------------------------------')
                cprint("%-25s %-80s %-30s %-7s" %(title_Fecha, title_Url, title_Estado, title_Tiempo),'white')
                print ('------------------------------------------------------------------------------------------------------------------------------------------------------')
        #Manejo de excepciones para timeout y otros errores     
        except ssl.SSLError as e:
                cantT+= 1   
                cprint("%-25s %-80s %-30s %-7s" %(time.strftime("%c"),site, e.reason, elapse_time),'yellow')
        except socket.timeout as e:
                    cantT+= 1
                    cprint("%-25s %-80s %-30s %-7s" %(time.strftime("%c"),site, "Timeout",TIMEOUT),'red')
        except urllib.error.URLError as e:
                if isinstance(e.reason, socket.timeout):
                    cantT+= 1
                    cprint("%-25s %-80s %-30s %-7s" %(time.strftime("%c"),site, "Timeout",TIMEOUT),'red')
                else:
                    cantT+= 1
                    cprint("%-25s %-80s %-30s %-7s" %(time.strftime("%c"),site, e.reason, elapse_time),'yellow')
        except SocketError as e:
                conn.close()
                cantT+= 1
                cprint("%-25s %-80s %-30s %-7s" %(time.strftime("%c"),site, e.reason , elapse_time),'red')
                #continue
        except ConnectionResetError as e:
                conn.close()
                cantT+= 1
                cprint("%-25s %-80s %-30s %-7s" %(time.strftime("%c"),site, e.reason , elapse_time),'red')
                #continue
        except urllib.request.HTTPError as e:
                cantT+= 1
                cprint("%-25s %-80s %-30s %-7s" %(time.strftime("%c"),site, e.reason,elapse_time),'red')

    #Cierre de conexion y sleep 
    time.sleep(2)
    #conn.close()