def delete(self, doc):
        if doc.id is None:
            raise DatabaseException('Document does not have id')
        if doc.sid is None:
            try:
                rs = self.db.docs.remove({'id': doc.id}, safe=True)
                assert rs['n'] == 1
            except Exception as e:
                raise DatabaseException(e)
            return None
        doc.data = None
        return self.update(doc)
def __init__(self, host, loginUser, debug = False, trace = False, log=None, port=22, pexpectObject=None):
        self.pexpect = pexpect if not pexpectObject else pexpectObject
        self.debug = debug
        self.trace = trace
        self.host = host
        self._port = port
        self._connection = None
        self.modeList = []
        self._log = log
        self._bufferedCommands = None
        self._bufferedMode = None
        self._loginUser = loginUser
        self._resetExpect()