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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 _ensure_content_type():
 """ Add the bulldog content type to the database if it's missing. """

    from django.contrib.contenttypes.models import ContentType
    try:
        row = ContentType.objects.get(app_label=PERM_APP_NAME)
    except ContentType.DoesNotExist:
        row = ContentType(name=PERM_APP_NAME, app_label=PERM_APP_NAME, model=PERM_APP_NAME)
        row.save()
    return row.id