  from django.db.models.lookups import (
      YearExact, YearGt, YearGte, YearLt, YearLte,
  )
  from django.utils import timezone
  from django.utils.functional import cached_property
  
  
  class TimezoneMixin:
      tzinfo = None
  
 
</s> remove     DateField, DateTimeField, DurationField, IntegerField, TimeField,
 </s> add     DateField, DateTimeField, DurationField, Field, IntegerField, TimeField, </s> remove     @cached_property
    def output_field(self):
        return IntegerField()

 </s> add  </s> remove     output_field_class = None
 </s> add  </s> remove         output_field = copy.output_field
        explicit_output_field = field.__class__ != copy.output_field.__class__
 </s> add         class_output_field = self.__class__.output_field if isinstance(self.__class__.output_field, Field) else None
        output_field = class_output_field or copy.output_field
        has_explicit_output_field = class_output_field or field.__class__ is not copy.output_field.__class__
  from django.db.models.lookups import (
      YearExact, YearGt, YearGte, YearLt, YearLte,
  )
  from django.utils import timezone

  
  
  class TimezoneMixin:
      tzinfo = None
  
keep keep keep keep replace keep keep keep keep keep
 Fixed #28492 -- Defined default output_field of expressions at the class level.

This wasn't possible when settings were accessed during Field initialization
time as our test suite setup script was triggering imports of expressions
before settings were configured. 
django/db/models/functions/datetime.py