def get_net_start(ipaddr, netmask):
 net = ipaddress.ip_network('{0}/{1}'.format(ipaddr, netmask), strict=False)
 return str(net.network_address)

def get_net_start ( ipaddr , netmask ) : net = ipaddress . ip_network ( '{0}/{1}' . format ( ipaddr , netmask ) , strict = False ) return str ( net . network_address )
return the address of the network .