datetime_fmt.py

from datetime import datetime

now = datetime.now()

codes = [
    r'%Y-%m-%d %H:%M:%S',
    r'%a %b %d %H:%M:%S',
    r'%A %B %d',
    r'%c',
    r'%x %X %z %Z',  # locale's date & time, UTC offset and timezone
]


print '%17s : %s' % ('code', 'result')
print '-'*17, ':', '-'*17
for c in codes:
    print '%17s : %s' % (c, now.strftime(c))

$ python datetime_fmt.py
             code : result
----------------- : -----------------
%Y-%m-%d %H:%M:%S : 2013-06-22 22:58:58
%a %b %d %H:%M:%S : Sat Jun 22 22:58:58
         %A %B %d : Saturday June 22
               %c : Sat Jun 22 22:58:58 2013
      %x %X %z %Z : 06/22/13 22:58:58