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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 handle_message(self, msg):
 """Issues an `inspection` service message based on a PyLint message. Registers each message type upon first encounter. :param utils.Message msg: a PyLint message """

        if msg.msg_id not in self.msg_types:
            self.report_message_type(msg)
            self.msg_types.add(msg.msg_id)

        self.tc.message('inspection', typeId=msg.msg_id, message=msg.msg,
                        file=os.path.relpath(msg.abspath).replace('\\', '/'),
                        line=str(msg.line),
                        SEVERITY=TC_SEVERITY.get(msg.category))