How to implement such logic on tastypie?

Question

Python

I'm trying to implement a Python / Django and Tastypie REST API , a regular check is taken as an example.
Given:
A receipt has:
- receipt number (unique value),
- date of receipt creation,
- date of last modification of the receipt (filled in by the application),
- total cost of goods,
- discount (filled in by the application),
- amount payable (filled in by the application),
- status (by default "Processed").
Upon POST request to the collection, the web service must:
- create a new receipt if the receipt number is missing in the sent data; otherwise, try to update an already existing check whose number matches the one sent
- in case of creating a new check, create a check number in the format "RCPT-<unique number>",
- calculate the amount of the discount as 3% of the total cost of the goods, and fill in the "discount" field with the received value,
- calculate the amount payable as the difference between the values ​​of the total cost of the goods and the discount; fill in the "Amount payable" field with the resulting value
- in case of creating a new receipt, and if the date/time of receipt creation is missing in the sent data, fill in the "date of receipt creation" field with the current date/time; if there is a check creation date in the sent data, save the sent date,
- in case of updating an existing check, keep the original check creation date regardless of the data sent,
- fill in the "check last modification date" field with the current date/time, ignoring any data sent,
- fill in the status field with the default value "Processed".
A web service on a GET request to a collection should return all checks with the "Processed" status. Checks with other statuses should be hidden.
The web service, upon request DELETE to a collection instance, should change the status of the selected receipt to the status "Canceled".
All other requests should be ignored by the web service.
Wrote:
retail/models.py:

import uuid
from django.db import models
from django.utils import timezone

class Receipt(models.Model):
    ''' Retail receipt '''
    number = models.CharField(max_length=20, unique=True, editable=False)
    full_price = models.FloatField()
    discount = models.FloatField()
    final_amount = models.FloatField()
    status = models.CharField(max_length=20, default='Обработан')

    created = models.DateTimeField()  # editable=True
    modified = models.DateTimeField()

    def __init__(self, *args, **kwargs):
        super(Receipt, self).__init__(*args, **kwargs)
        # "RCPT-<уникальный номер>"
        self.number = 'RCPT-' + uuid.uuid4().hex
                
    def save(self, *args, **kwargs):
        ''' On save, update timestamps '''
        self.modified = timezone.now()
        if not self.id:
            self.created = self.modified
        return super(Receipt, self).save(*args, **kwargs)

retail/api.py:

from tastypie.resources import ModelResource
from tastypie.authorization import Authorization
from retail.models import Receipt

class ReceiptResource(ModelResource):
    class Meta:
        queryset = Receipt.objects.all()
        list_allowed_methods = ['get', 'post', 'delete']
        resource_name = 'receipt'
        authorization = Authorization()
#        filtering = {
#            'status': ['Обработан'],
#        }

        def get_object_list(self, request):
            # .filter(status='Обработан') -  это ничего не дало
            return super(ReceiptResource, self).get_object_list(request).filter(status='Обработан')

myapp/urls.py:

from django.conf.urls import url, include
from django.contrib import admin
from retail.api import ReceiptResource

receipt_resource = ReceiptResource()

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^api/', include(receipt_resource.urls)),
]

Working with dates seems to meet the requirements, the number too, but filtering by status, performing any logic on POST / GET / DELETE requests - how to do this?
Please tell me what I need in Tastypie to implement this. The third day I search in the documentation "that, without knowing that".