'Initialize the OpenID middleware
``app``
Your WSGI app to call
``data_store_path``
Directory to store crypto data in for use with OpenID servers.
``auth_prefix``
Location for authentication process/verification
``login_redirect``
Location to load after successful process of login
``catch_401``
If true, then any 401 responses will turn into open ID login
requirements.
``url_to_username``
A function called like ``url_to_username(environ, url)``, which should
return a string username.  If not given, the URL will be the username.'

def __init__(self, app, data_store_path, auth_prefix='/oid', login_redirect=None, catch_401=False, url_to_username=None):

    store = filestore.FileOpenIDStore(data_store_path)
    self.oidconsumer = consumer.OpenIDConsumer(store)
    self.app = app
    self.auth_prefix = auth_prefix
    self.data_store_path = data_store_path
    self.login_redirect = login_redirect
    self.catch_401 = catch_401
    self.url_to_username = url_to_username
