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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 delete_all_from_db():
 """Clear the database. Used for testing and debugging. """

    # The models.CASCADE property is set on all ForeignKey fields, so tables can
    # be deleted in any order without breaking constraints.
    for model in django.apps.apps.get_models():
        model.objects.all().delete()