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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 _write(self, body, id):
 """ Respond to a WRITE command, sending some data over a virtual channel created by VIRTUAL. The answer is simply an acknowledgement, as it is simply meant to note that the write went through without errors. An occurrence of I{Write} on the wire, together with the response generated by this method, might have this apperance:: C: -Command: Write C: -Ask: 1 C: -Length: 13 C: Id: glyph@divmod.com->radix@twistedmatrix.com:q2q-example:0 C: C: HELLO WORLD C: S: -Answer: 1 S: """

        if id not in self.connections:
            raise error.ConnectionDone()
        connection = self.connections[id]
        connection.dataReceived(body)
        return {}