def auth_none(self, username):
if (not self.active) or (not self.initial_kex_done):<EOL><INDENT>raise SSHException("<STR_LIT>")<EOL><DEDENT>my_event = threading.Event()<EOL>self.auth_handler = AuthHandler(self)<EOL>self.auth_handler.auth_none(username, my_event)<EOL>return self.auth_handler.wait_for_response(my_event)<EOL>
Try to authenticate to the server using no authentication at all.
This will almost always fail.  It may be useful for determining the
list of authentication types supported by the server, by catching the
`.BadAuthenticationType` exception raised.

:param str username: the username to authenticate as
:return:
    list of auth types permissible for the next stage of
    authentication (normally empty)

:raises:
    `.BadAuthenticationType` -- if "none" authentication isn't allowed
    by the server for this user
:raises:
    `.SSHException` -- if the authentication failed due to a network
    error

.. versionadded:: 1.5