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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 _on_trace(self, sequence, topic, message):
 """Process a trace received from a device. Args: sequence (int):
 The sequence number of the packet received topic (string):
 The topic this message was received on message (dict):
 The message itself """


        try:
            conn_key = self._find_connection(topic)
            conn_id = self.conns.get_connection_id(conn_key)
        except ArgumentError:
            self._logger.warn("Dropping trace message that does not correspond with a known connection, topic=%s", topic)
            return

        try:
            tracing = messages.TracingNotification.verify(message)
            self._trigger_callback('on_trace', conn_id, tracing['trace'])
        except Exception:
            self._logger.exception("Error processing trace conn_id=%d", conn_id)