Searches auth.log for failed logins and adds them to hosts.deny. Probably a terrible way to do it, and it's potentially a massive failure. But i'm sick of fail2ban not banning

authlog.py

#!/usr/bin/env python

authlog=open('/var/log/auth.log','r')

lines = []
for line in authlog:
    lines.append(line)

authlog.close()

failedAttempts = []
for line in lines:
    try:
        x = line.split('Failed password for')[1]
    except IndexError:
        1 + 1
    else:
        failedAttempts.append(x)

ips = []
for failedAttempt in failedAttempts:
    attempt = failedAttempt.split(' ')[1]
    if attempt == 'invalid':
        ips.append(failedAttempt.split(' ')[5])
    elif attempt == 'root':
        ips.append(failedAttempt.split(' ')[3])
    else:
        2 + 4

ips = sorted(set(ips))

# hostsDeny line 20 is start of IPs
hostsDeny=open('/etc/hosts.deny', 'r')
tempdenys = []
for line in hostsDeny:
    tempdenys.append(line)
# close hostsdeny
hostsDeny.close()

denys = []
newIPs = []

for x in range(20, len(tempdenys)):
    denys.append(tempdenys[x])

hostsDenyWrite = file('/etc/hosts.deny', 'a')
for ip in ips:
    ipCheck = ip + '\n'
    if ipCheck not in denys:
        print ip
        hostsDenyWrite.write(ip + '\n')


hostsDenyWrite.close()