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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 _close(self, id):
 """ Respond to a CLOSE command, dumping some data onto the stream. As with WRITE, this returns an empty acknowledgement. An occurrence of I{Close} on the wire, together with the response generated by this method, might have this apperance:: C: -Command: Close C: -Ask: 1 C: Id: glyph@divmod.com->radix@twistedmatrix.com:q2q-example:0 C: S: -Answer: 1 S: """

        # The connection is removed from the mapping by connectionLost.
        connection = self.connections[id]
        connection.connectionLost(Failure(CONNECTION_DONE))
        return {}