viewthing.py

import web
from exceptions import ValueError

urls = ('/', 'Index')

store_url = 'No_url'

class Index:

    def GET(self):
        return store_url

    def POST(self, url=None):
        if url:
            store_url = url
            return 'success'
        else:
            raise ValueError('No url provided')

app = web.application(urls, globals())

if __name__ == '__main__':
    app.run()