[Django]-Django circular import in models

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Is there a way I can get around this so that I can do the receipt query in the Employee property?

Yes, you can import the module in the method:

from django.db import models

class Employee(models.Model):
    number = models.CharField(max_length=50, unique=True)
    first_name = models.CharField(max_length=255)
    last_name = models.CharField(max_length=255)

    @property
    def receipt_sum(self):
        from receipts.models import Receipt
        receipts = Receipt.objects.filter(Employee=self.pk)
        sum = 0
        for receipt in receipts:
            sum += receipt.amount
        return sum

but it is actually not necessary to import Receipt at all, you can make use of the receipt_employee relation to access the related Receipt object, and you can use .aggregate(…) [Django-doc] to sum up the elements at the database side, this is likely more efficient:

from django.db import models
from django.db.models import Sum

class Employee(models.Model):
    number = models.CharField(max_length=50, unique=True)
    first_name = models.CharField(max_length=255)
    last_name = models.CharField(max_length=255)

    @property
    def receipt_sum(self):
        return self.receipt_employee.aggregate(
            total=Sum('amount')
        )['total'] or 0
👤willeM_ Van Onsem

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