Something

list = ['120.226.50.70.in-addr.arpa', '53.180.186.205.in-addr.arpa', '134.136.51.204.in-addr.arpa', '1.104.183.206.in-addr.arpa', '117.62.25.70.in-addr.arpa', '119.254.159.69.in-addr.arpa', '198.171.128.174.in-addr.arpa', '255.194.159.69.in-addr.arpa', '201.37.20.201.in-addr.arpa', '80.251.14.74.in-addr.arpa', '31.11.28.70.in-addr.arpa', '197.120.52.70.in-addr.arpa', '10.202.204.41.in-addr.arpa', '215.49.76.201.in-addr.arpa', '33.187.54.70.in-addr.arpa', '32.162.90.69.in-addr.arpa', '55.217.45.187.in-addr.arpa', '209.206.65.76.in-addr.arpa', '241.155.92.85.in-addr.arpa', '238.202.204.41.in-addr.arpa', '242.103.225.173.in-addr.arpa', '155.56.25.70.in-addr.arpa', '99.142.90.189.in-addr.arpa', '251.99.26.94.in-addr.arpa', '147.78.25.70.in-addr.arpa']

import adns
dns = adns.init()
checking = []
for addr in list:
	obj = dns.submit(addr, adns.rr.PTR)
	checking.append(obj)

for i in checking:
	try: i.check()
	except: pass

checking = [] # Freezes on these two lines
list = []