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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 _validate_entity_cls(self, entity_cls):
 """Validate that Entity is a valid class"""

        # Import here to avoid cyclic dependency
        from protean.core.entity import Entity

        if not issubclass(entity_cls, Entity):
            raise AssertionError(
                f'Entity {entity_cls.__name__} must be subclass of `Entity`')

        if entity_cls.meta_.abstract is True:
            raise NotSupportedError(
                f'{entity_cls.__name__} class has been marked abstract'
                f' and cannot be instantiated')