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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_links(network_id, template_id=None):
 """ Get all the links in a network """

    extras = {'types':[], 'attributes':[]}
    link_qry = db.DBSession.query(Link).filter(
                                        Link.network_id==network_id,
                                        Link.status=='A').options(
                                            noload('network')
                                        )
    if template_id is not None:
        link_qry = link_qry.filter(ResourceType.link_id==Link.id,
                                   TemplateType.id==ResourceType.type_id,
                                   TemplateType.template_id==template_id)

    link_res = db.DBSession.execute(link_qry.statement).fetchall()

    links = []
    for l in link_res:
        links.append(JSONObject(l, extras=extras))

    return links