How to extract timing info like HH:MM:SS from a given list using for loop in Python without importing any module
Question: 
    ['From', 'stephen.marquard@uct.ac.za', 'Sat', 'Jan', '5', '09:14:16', '2008',
     'From:', 'stephen.marquard@uct.ac.za', 'From', 'louis@media.berkeley.edu',
     'Fri', 'Jan', '4', '18:10:48', '2008', 'From:', 'louis@media.berkeley.edu',
     'From', 'zqian@umich.edu', 'Fri', 'Jan', '4', '16:10:39', '2008', 'From:',
     'zqian@umich.edu', 'From', 'rjlowe@iupui.edu', 'Fri', 'Jan', '4', '15:46:24',
     '2008', 'From:', 'rjlowe@iupui.edu', 'From', 'zqian@umich.edu', 'Fri', 'Jan',
     '4', '15:03:18', '2008', 'From:', 'zqian@umich.edu', 'From',
     'rjlowe@iupui.edu', 'Fri', 'Jan', '4', '14:50:18', '2008', 'From:',
     'rjlowe@iupui.edu', 'From', 'cwen@iupui.edu', 'Fri', 'Jan', '4', '11:37:30',
     '2008', 'From:', 'cwen@iupui.edu', 'From', 'cwen@iupui.edu', 'Fri', 'Jan', '4',
     '11:35:08', '2008', 'From:', 'cwen@iupui.edu', 'From', 'gsilver@umich.edu',
     'Fri', 'Jan', '4', '11:12:37', '2008', 'From:', 'gsilver@umich.edu', 'From',
     'gsilver@umich.edu', 'Fri', 'Jan', '4', '11:11:52', '2008', 'From:',
     'gsilver@umich.edu', 'From', 'zqian@umich.edu', 'Fri', 'Jan', '4', '11:11:03',
     '2008', 'From:', 'zqian@umich.edu', 'From', 'gsilver@umich.edu', 'Fri', 'Jan',
     '4', '11:10:22', '2008', 'From:', 'gsilver@umich.edu', 'From',
     'wagnermr@iupui.edu', 'Fri', 'Jan', '4', '10:38:42', '2008', 'From:',
     'wagnermr@iupui.edu', 'From', 'zqian@umich.edu', 'Fri', 'Jan', '4', '10:17:43',
     '2008', 'From:', 'zqian@umich.edu', 'From', 'antranig@caret.cam.ac.uk', 'Fri',
     'Jan', '4', '10:04:14', '2008', 'From:', 'antranig@caret.cam.ac.uk', 'From',
     'gopal.ramasammycook@gmail.com', 'Fri', 'Jan', '4', '09:05:31', '2008',
     'From:', 'gopal.ramasammycook@gmail.com', 'From', 'david.horwitz@uct.ac.za',
     'Fri', 'Jan', '4', '07:02:32', '2008', 'From:', 'david.horwitz@uct.ac.za',
     'From', 'david.horwitz@uct.ac.za', 'Fri', 'Jan', '4', '06:08:27', '2008',
     'From:', 'david.horwitz@uct.ac.za', 'From', 'david.horwitz@uct.ac.za',]
    

Is there any of extracting a string of specific type like hh:mm:ss from a
list? I want to extract this information without importing any module.


Answer: RegEx way:

    
    
    >>> [i for i in your_list if re.match('\d{2}:\d{2}:\d{2}', i)]
    ['09:14:16', '18:10:48', '16:10:39', 
     '15:46:24', '15:03:18', '14:50:18', 
     '11:37:30', '11:35:08', '11:12:37', 
     '11:11:52', '11:11:03', '11:10:22', 
     '10:38:42', '10:17:43', '10:04:14', 
     '09:05:31', '07:02:32', '06:08:27', 
     '04:49:08', '04:33:44', '04:07:34', 
     '19:51:21', '17:18:23', '17:07:00', 
     '16:34:40', '16:29:07', '16:23:48']
    >>> 
    

