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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_scenarios(network_id,**kwargs):
 """ Get all the scenarios in a given network. """


    user_id = kwargs.get('user_id')
    try:
        net_i = db.DBSession.query(Network).filter(Network.id == network_id).one()
        net_i.check_read_permission(user_id=user_id)
    except NoResultFound:
        raise ResourceNotFoundError("Network %s not found"%(network_id))

    return net_i.scenarios