  
  from django.core.cache import cache
  from django.core.exceptions import SuspiciousFileOperation
  from django.core.files.base import ContentFile, File
  from django.core.files.storage import FileSystemStorage, get_storage_class
  from django.core.files.uploadedfile import (
      InMemoryUploadedFile, SimpleUploadedFile, TemporaryUploadedFile,
  )
  from django.db.models.fields.files import FileDescriptor
  from django.test import (
 
</s> remove from django.core.files.storage import default_storage
 </s> add from django.core.files.storage import Storage, default_storage
from django.core.files.storage import (
    FileSystemStorage, Storage as BaseStorage, get_storage_class,
)
  
  from django.core.cache import cache
  from django.core.exceptions import SuspiciousFileOperation
  from django.core.files.base import ContentFile, File
from django.core.files.storage import (
    FileSystemStorage, Storage as BaseStorage, get_storage_class,
)
  from django.core.files.uploadedfile import (
      InMemoryUploadedFile, SimpleUploadedFile, TemporaryUploadedFile,
  )
  from django.db.models.fields.files import FileDescriptor
  from django.test import (
keep keep keep keep replace keep keep keep keep keep
 Fixed #28184 -- Allowed using a callable for FileField and ImageField storage. 
tests/file_storage/tests.py