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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 create_invoice_from_ticket(pk, list_lines):
 """ la pk y list_lines son de ticket, necesitamos la info de las lineas de pedidos """

        context = {}
        if list_lines:
            new_list_lines = [x[0] for x in SalesLineTicket.objects.values_list('line_order__pk').filter(pk__in=[int(x) for x in list_lines])]
            if new_list_lines:
                lo = SalesLineOrder.objects.values_list('order__pk').filter(pk__in=new_list_lines)[:1]
                if lo and lo[0] and lo[0][0]:
                    new_pk = lo[0][0]
                    return GenLineProduct.create_invoice_from_order(new_pk, new_list_lines)
                else:
                    error = _('Pedido no encontrado')
            else:
                error = _('Lineas no relacionadas con pedido')
        else:
            error = _('Lineas no seleccionadas')
        context['error'] = error
        return context