How to access related values with select_related() - django

Question

I have a QuerySet that I'm attempting to work with the values on related tables. I see the related tables/values when I run the queryset.query, however I'm not sure how to pull those values for use in forms/tables.
Here is my QuerySet Object:
tpList = AppCustomerTpRel.objects.filter(idcst_rel=selection).select_related('idcst_rel', 'idtrp_rel').values()
Here are the related Models.
class AppCustomerTpRel(models.Model):
id_rel = models.AutoField(primary_key=True)
idcst_rel = models.ForeignKey(AppCustomerCst, models.DO_NOTHING, db_column='idcst_rel')
idtrp_rel = models.ForeignKey(AppTradingPartnerTrp, models.DO_NOTHING, db_column='idtrp_rel')
cust_vendor_rel = models.CharField(max_length=50, blank=True, null=True)
sender_id_rel = models.CharField(max_length=50, blank=True, null=True)
old_vendor_rel = models.CharField(max_length=50, blank=True, null=True)
vendor_name_rel = models.CharField(max_length=50, blank=True, null=True)
category_rel = models.CharField(max_length=50, blank=True, null=True)
class AppTradingPartnerTrp(models.Model):
id_trp = models.AutoField(primary_key=True)
tpid_trp = models.CharField(max_length=50, blank=True, null=True)
name_trp = models.CharField(max_length=50)
description_trp = models.CharField(max_length=100, blank=True, null=True)
idtrn_trp = models.ForeignKey('AppTransmissionTrn', models.DO_NOTHING, db_column='idtrn_trp', blank=True, null=True)
class AppCustomerCst(models.Model):
id_cst = models.AutoField(primary_key=True)
is_active_cst = models.BooleanField()
name_cst = models.CharField(max_length=50, blank=True, null=True)
address_1_cst = models.CharField(max_length=50, blank=True, null=True)
address_2_cst = models.CharField(max_length=50, blank=True, null=True)
address_3_cst = models.CharField(max_length=50, blank=True, null=True)
city_cst = models.CharField(max_length=50, blank=True, null=True)
state_cst = models.CharField(max_length=50, blank=True, null=True)
zip_cst = models.CharField(max_length=10, blank=True, null=True)
country_cst = models.CharField(max_length=50, blank=True, null=True)
salesrep_cst = models.CharField(max_length=50, blank=True, null=True)
type_cst = models.CharField(max_length=10, blank=True, null=True)
is_allowed_flat_cst = models.BooleanField()
iddef_cst = models.IntegerField()
date_created_cst = models.DateTimeField()
date_suspended_cst = models.DateTimeField(blank=True, null=True)
date_first_tran_cst = models.DateTimeField(blank=True, null=True)
date_last_tran_cst = models.DateTimeField(blank=True, null=True)
is_credit_hold_cst = models.BooleanField()
old_balance_cst = models.DecimalField(max_digits=8, decimal_places=2)
balance_notify_cst = models.DecimalField(max_digits=8, decimal_places=2)
balance_statement_cst = models.DecimalField(max_digits=8, decimal_places=2)
balance_conversion_cst = models.DecimalField(max_digits=8, decimal_places=2)
balance_cst = models.DecimalField(max_digits=8, decimal_places=2)
receive_emails_cst = models.BooleanField()
contact_domain_cst = models.CharField(max_length=100, blank=True, null=True)
I am trying to work with values from the 'AppCustomerTpRel' Table.
I have tried app_customer_tp_rel.id_rel as well as app_customer_tp_rel__id_rel with the SQL Table Names, I have also tried both using the Model Name AppCustomerTpRel
TIA!

Answer 1

Just wright all related fields the you need in values()
tpList = AppCustomerTpRel.objects.filter(
idcst_rel=selection
).select_related(
'idcst_rel',
'idtrp_rel'
).values(
'idtrp_rel__id_trp',
'idtrp_rel__tpid_trp',
'idtrp_rel__name_trp',
...
)