pretty python datetime formatting

python_format_datetime.py

def format_datetime(datetime, format_name="nice short",
                    custom_format=None, convert_bst=True):
    """
    Jinja2 filter to turn a datetime into a string

    `datetime` must be timezone-naive (as far as python is concerned),
    but its values must be UTC.

    Either pick `format_name` from the options below, or provide
    `custom_format`

    * ``full+tz``: 2013-08-07 18:23:46 BST+0100
    * ``full``: 2013-08-07 18:24:12
    * ``nice``: Wednesday 07 August 2013 at 18:24:37
    * ``nice short``: Wed 07 Aug at 18:24
    * ``date``: 2013-08-07
    * ``date nice``: Wednesday 07 August 2013
    * ``date nice short``: Wed 07 Aug

    """                                     
                                                
    formats = {
        "full+tz": "%Y-%m-%d %H:%M:%S %Z%z",        
        "full": "%Y-%m-%d %H:%M:%S",                    
        "nice": "%A %d %B %Y at %H:%M:%S",                  
        "nice short": "%a %d %b at %H:%M",                      
        "date": "%Y-%m-%d",                                         
        "date nice": "%A %d %B %Y",                                     
        "date nice short": "%a %d %b",                                      
    }
                                                                                
    if custom_format is not None:
        format = custom_format
    else:
        format = formats[format_name]

    datetime = pytz.utc.localize(datetime)
    if convert_bst:
        datetime = datetime.astimezone(pytz_bst)

    return datetime.strftime(format)