how to apply "mvc" pattern to gui-design in python

i have a project want to develop with python. who can tell me that how to apply "mvc" pattern to gui-design in python. please give me some advices! ths in advanced. -- 蓦然回首曾经岁月， 朦胧中依稀闪烁着清晰。 才发现， 原来在我的记忆深处， 还残留着宁静而又幸福的瞬间。 一世风流已飘过，转眼渐成白头翁。 -- http://mail.python.org/mailman/listinfo/python-list

why and when we should do it?

hi,everybody,Sorry to bother you. i hvae seen some code like this before: class BusinessBO : dev __init__(slef): #write you own code here dev businessMethod : #write you own code here pass why and when we should add the keyword "pass" ? and some time i have seen class S