'Gets the session ID for a client given the client dictionary
Args:
clientdict: The dictionary sent by the client in the request
Returns:
str|None: The string session ID the client sent. If the client did
not send a session ID, returns None.'

def get_session_id(self, clientdict):

    sid = None
    if (clientdict and ('auth' in clientdict)):
        authdict = clientdict['auth']
        if ('session' in authdict):
            sid = authdict['session']
    return sid
