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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def redirectURL(self, realm, return_to=None, immediate=False):
 """Returns a URL with an encoded OpenID request. The resulting URL is the OpenID provider's endpoint URL with parameters appended as query arguments. You should redirect the user agent to this URL. OpenID 2.0 endpoints also accept POST requests, see C{L{shouldSendRedirect}} and C{L{formMarkup}}. @param realm: The URL (or URL pattern) that identifies your web site to the user when she is authorizing it. @type realm: str @param return_to: The URL that the OpenID provider will send the user back to after attempting to verify her identity. Not specifying a return_to URL means that the user will not be returned to the site issuing the request upon its completion. @type return_to: str @param immediate: If True, the OpenID provider is to send back a response immediately, useful for behind-the-scenes authentication attempts. Otherwise the OpenID provider may engage the user before providing a response. This is the default case, as the user may need to provide credentials or approve the request before a positive response can be sent. @type immediate: bool @returns: The URL to redirect the user agent to. @returntype: str """

        message = self.getMessage(realm, return_to, immediate)
        return message.toURL(self.endpoint.server_url)