  from django import forms
  from django.core import checks
  from django.core.files.base import File
  from django.core.files.images import ImageFile
  from django.core.files.storage import default_storage
  from django.db.models import signals
  from django.db.models.fields import Field
  from django.utils.translation import gettext_lazy as _
  
  
 
</s> remove from django.core.files.storage import FileSystemStorage, get_storage_class
 </s> add from django.core.files.storage import (
    FileSystemStorage, Storage as BaseStorage, get_storage_class,
)
from django.core.files.storage import Storage, default_storage
  from django import forms
  from django.core import checks
  from django.core.files.base import File
  from django.core.files.images import ImageFile
from django.core.files.storage import Storage, default_storage
  from django.db.models import signals
  from django.db.models.fields import Field
  from django.utils.translation import gettext_lazy as _
  
  
keep keep keep keep replace keep keep keep keep keep
 Fixed #28184 -- Allowed using a callable for FileField and ImageField storage. 
django/db/models/fields/files.py