Python code: python acting like awk

hi all,

I am really love to use unix utility such as "awk". It is useful when I wish to retrieve a certain column in a delimited file, e.g. /etc/passwd. I believe everyone should know. It is simple and easy.

root@lynx-vm:~# cat /etc/passwd | awk -F":" '{print $1}'
root
daemon
bin
sys
sync
games
man
lp
mail
news
uucp
proxy

However, I would like to show you on how to get it done with Python. Personally, I have struggled a lot when doing a similar operation in unix command, as compared in Python. Hope that small tricks could save your times.

>>>
>>>
>>> passwdlines = [ line.split(":") for line in open("/etc/passwd") if "#" not in line]
>>> passwdlines[:5]
[['root', 'x', '0', '0', 'root', '/root', '/bin/bash\n'], ['daemon', 'x', '1', '1', 'daemon', '/usr/sbin', '/usr/sbin/nologin\n'], ['bin', 'x', '2', '2', 'bin', '/bin', '/usr/sbin/nologin\n'], ['sys', 'x', '3', '3', 'sys', '/dev', '/usr/sbin/nologin\n'], ['sync', 'x', '4', '65534', 'sync', '/bin', '/bin/sync\n']]
>>> 

If you would like to know the first column.
>>>
>>> firstcolumn = [column[0] for column in passwdlines]
>>>
>>>
>>> firstcolumn[:5]
['root', 'daemon', 'bin', 'sys', 'sync']
>>> 

If you would like to know the line contains "root".
>>>
>>> rootline = [ line for line in passwdlines if "root" in line]
>>>
>>>
>>> rootline
[['root', 'x', '0', '0', 'root', '/root', '/bin/bash\n']]