gistfile1.py

from django.db import models

class CustomQuerySetManager(models.Manager):
    use_for_related_fields = True
    
    def __init__(self, queryset, *args, **kwargs):
        super(CustomQuerySetManager, self).__init__(*args, **kwargs)
        self._queryset = queryset
    
    def get_query_set(self):
        return self._queryset(self.model, using=self._db)
    
    def __getattr__(self, attr):
        try:
            return getattr(self.__class__, attr)
        except AttributeError:
            return getattr(self.get_query_set(), attr)