from datetime import datetime

class Base(object):

date_format = '%Y-%m-%d'

time_format = '%H:%M:%S'

datetime_format = date_format + 'T%s' % time_format

full_datetime_format = date_format + 'T' + time_format + '.%f'

iso_format = date_format + 'T%sZ' % time_format

standard_datetime_format = date_format + ' ' + time_format

extended_datetime_format = date_format + 'T' + time_format +'.%fZ'

@classmethod

def parse_date_time(cls, text):

instance = None

formats = [cls.extended_datetime_format, cls.full_datetime_format, cls.datetime_format, cls.standard_datetime_format, cls.iso_format, cls.date_format]

for format in formats:

try:

instance = datetime.strptime(text, format)

except Exception:

pass

else:

break

return instance