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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def modify(self, failed, deliverable, annotations=None):
 """Send a response disposition to the service to indicate that a received message has been modified. If the client is running in PeekLock mode, the service will wait on this disposition. Otherwise it will be ignored. Returns `True` is message was modified, or `False` if the message was already settled. :param failed: Whether this delivery of this message failed. This does not indicate whether subsequence deliveries of this message would also fail. :type failed: bool :param deliverable: Whether this message will be deliverable to this client on subsequent deliveries - i.e. whether delivery is retryable. :type deliverable: bool :param annotations: Annotations to attach to response. :type annotations: dict :rtype: bool :raises: TypeError if the message is being sent rather than received. """

        if self._can_settle_message():
            self._response = errors.MessageModified(
                failed,
                deliverable,
                annotations=annotations,
                encoding=self._encoding)
            self._settler(self._response)
            self.state = constants.MessageState.ReceivedSettled
            return True
        return False