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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 register(cls, name, entrypoint):
 """ Register a new entrypoint :param str name: Key used by messages :param kser.entry.Entrypoint entrypoint: class to load :raises ValidationError: Invalid entry """

        if not issubclass(entrypoint, Entrypoint):
            raise ValidationError(
                "Invalid type for entry '{}', MUST implement "
                "kser.entry.Entrypoint".format(name),
                extra=dict(entrypoint=name)
            )
        cls.ENTRYPOINTS[name] = entrypoint
        logger.debug("{}.Registered: {}".format(cls.__name__, name))