<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _x_start_ok(self, client_properties, mechanism, response, locale):
 """ select security mechanism and locale This method selects a SASL security mechanism. ASL uses SASL (RFC2222) to negotiate authentication and encryption. PARAMETERS: client_properties: table client properties mechanism: shortstr selected security mechanism A single security mechanisms selected by the client, which must be one of those specified by the server. RULE: The client SHOULD authenticate using the highest- level security profile it can handle from the list provided by the server. RULE: The mechanism field MUST contain one of the security mechanisms proposed by the server in the Start method. If it doesn't, the server MUST close the socket. response: longstr security response data A block of opaque data passed to the security mechanism. The contents of this data are defined by the SASL security mechanism. For the PLAIN security mechanism this is defined as a field table holding two fields, LOGIN and PASSWORD. locale: shortstr selected message locale A single message local selected by the client, which must be one of those specified by the server. """

        args = AMQPWriter()
        args.write_table(client_properties)
        args.write_shortstr(mechanism)
        args.write_longstr(response)
        args.write_shortstr(locale)
        self._send_method((10, 11), args)