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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 app_authenticate(self, account=None, flush=True, bailout=False):
 """ Attempt to perform application-level authentication. Application level authentication is needed on devices where the username and password are requested from the user after the connection was already accepted by the remote device. The difference between app-level authentication and protocol-level authentication is that in the latter case, the prompting is handled by the client, whereas app-level authentication is handled by the remote device. App-level authentication comes in a large variety of forms, and while this method tries hard to support them all, there is no guarantee that it will always work. We attempt to smartly recognize the user and password prompts; for a list of supported operating systems please check the Exscript.protocols.drivers module. Returns upon finding the first command line prompt. Depending on whether the flush argument is True, it also removes the prompt from the incoming buffer. :type account: Account :param account: An account object, like login(). :type flush: bool :param flush: Whether to flush the last prompt from the buffer. :type bailout: bool :param bailout: Whether to wait for a prompt after sending the password. """

        with self._get_account(account) as account:
            user = account.get_name()
            password = account.get_password()
            self._dbg(1, "Attempting to app-authenticate %s." % user)
            self._app_authenticate(account, password, flush, bailout)
        self.app_authenticated = True