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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 doc(model):
 """ Get documentation object for an SqlAlchemy model :param model: Model :type model: sqlalchemy.ext.declarative.DeclarativeBase :rtype: SaModelDoc """

    ins = inspect(model)

    return SaModelDoc(
        name=model.__name__,
        table=[t.name for t in ins.tables],
        doc=getdoc(ins.class_),
        columns=_model_columns(ins),
        primary=_model_primary(ins),
        foreign=_model_foreign(ins),
        unique=_model_unique(ins),
        relations=_model_relations(ins)
    )