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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 _get_queryset(klass):
 """ Returns a QuerySet from a Model, Manager, or QuerySet. Created to make get_object_or_404 and get_list_or_404 more DRY. Raises a ValueError if klass is not a Model, Manager, or QuerySet. """

    if isinstance(klass, QuerySet):
        return klass
    elif isinstance(klass, Manager):
        manager = klass
    elif isinstance(klass, ModelBase):
        manager = klass._default_manager
    else:
        if isinstance(klass, type):
            klass__name = klass.__name__
        else:
            klass__name = klass.__class__.__name__
        raise ValueError(
            "Object is of type '{}', but must be a Django Model, "
            "Manager, or QuerySet".format(klass__name)
        )
    return manager.all()