<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_smt_userid():
 """Get the userid of smt server"""

    cmd = ["sudo", "/sbin/vmcp", "query userid"]
    try:
        userid = subprocess.check_output(cmd,
                                         close_fds=True,
                                         stderr=subprocess.STDOUT)
        userid = bytes.decode(userid)
        userid = userid.split()[0]
        return userid
    except Exception as err:
        msg = ("Could not find the userid of the smt server: %s") % err
        raise exception.SDKInternalError(msg=msg)