  from django.core.files.storage import default_storage
  from django.core.validators import validate_image_file_extension
  from django.db.models import signals
  from django.db.models.fields import Field
  from django.utils import six
  from django.utils.encoding import force_str, force_text
  from django.utils.translation import ugettext_lazy as _
  
  
  class FieldFile(File):
 
</s> remove from django.utils import six
 </s> add  </s> remove from django.utils import six
 </s> add  </s> remove from django.utils import six
 </s> add  </s> remove from django.utils import six
 </s> add  </s> remove from django.utils import six
 </s> add 
  from django.core.files.storage import default_storage
  from django.core.validators import validate_image_file_extension
  from django.db.models import signals
  from django.db.models.fields import Field

  from django.utils.encoding import force_str, force_text
  from django.utils.translation import ugettext_lazy as _
  
  
  class FieldFile(File):
keep keep keep keep replace keep keep keep keep keep
 Refs #23919 -- Removed six.<various>_types usage

Thanks Tim Graham and Simon Charette for the reviews. 
django/db/models/fields/files.py