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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 _prune_hit(hit, model):
 """ Check whether a document should be pruned. This method uses the SearchDocumentManagerMixin.in_search_queryset method to determine whether a 'hit' (search document) should be pruned from an index, and if so it returns the hit as a Django object(id=hit_id). Args: hit: dict object the represents a document as returned from the scan_index function. (Contains object id and index.) model: the Django model (not object) from which the document was derived. Used to get the correct model manager and bulk action. Returns: an object of type model, with id=hit_id. NB this is not the object itself, which by definition may not exist in the underlying database, but a temporary object with the document id - which is enough to create a 'delete' action. """

    hit_id = hit["_id"]
    hit_index = hit["_index"]
    if model.objects.in_search_queryset(hit_id, index=hit_index):
        logger.debug(
            "%s with id=%s exists in the '%s' index queryset.", model, hit_id, hit_index
        )
        return None
    else:
        logger.debug(
            "%s with id=%s does not exist in the '%s' index queryset and will be pruned.",
            model,
            hit_id,
            hit_index,
        )
        # we don't need the full obj for a delete action, just the id.
        # (the object itself may not even exist.)
        return model(pk=hit_id)