<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def close(self, get_attributes=False, send=True):
 """ Closes an opened file. Supports out of band send function, call this function with send=False to return a tuple of (SMB2CloseRequest, receive_func) instead of sending the the request and waiting for the response. The receive_func can be used to get the response from the server by passing in the Request that was used to sent it out of band. :param get_attributes: (Bool) whether to get the latest attributes on the close and set them on the Open object :param send: Whether to send the request in the same call or return the message to the caller and the unpack function :return: SMB2CloseResponse message received from the server """

        # it is already closed and this isn't for an out of band request
        if not self._connected and send:
            return

        close = SMB2CloseRequest()

        close['file_id'] = self.file_id
        if get_attributes:
            close['flags'] = CloseFlags.SMB2_CLOSE_FLAG_POSTQUERY_ATTRIB

        if not send:
            return close, self._close_response

        log.info("Session: %s, Tree Connect: %s - sending SMB2 Close Request "
                 "for file %s" % (self.tree_connect.session.username,
                                  self.tree_connect.share_name,
                                  self.file_name))
        log.debug(str(close))
        request = self.connection.send(close,
                                       self.tree_connect.session.session_id,
                                       self.tree_connect.tree_connect_id)
        return self._close_response(request)