def datetime(value, format_str='<STR_LIT>'):
return value.strftime(format_str)<EOL>
Convert a datetime to a different format.

The default format looks like --> 2016/11/25 12:34

Args:
    value (datetime.datetime): input date and time
    format_str (str): The datetime format string to apply to value

Returns:
    str: value, after the format_str has been applied