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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 enter(self):
 """Send a LineConfirmation to the controller. When this state is entered, a :class:`AYABInterface.communication.host_messages.LineConfirmation` is sent to the controller. Also, the :attr:`last line requested <AYABInterface.communication.Communication.last_requested_line_number>` is set. """

        self._communication.last_requested_line_number = self._line_number
        self._communication.send(LineConfirmation, self._line_number)