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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 update_slugs(apps, schema_editor):
 """ Include birthdate in slugs """


    # Get model managers
    Representative = apps.get_model("representatives", "Representative")

    for rep in Representative.objects.all():
        rep.slug = '%s-%s' % (rep.slug, rep.birth_date)
        rep.save()