  import copy
  import datetime
  from django.utils import six
  from django.db.backends.schema import BaseDatabaseSchemaEditor
  from django.db.utils import DatabaseError
  
  
  class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
 
</s> remove from django.utils.http import urlquote
 </s> add  </s> remove from django.utils import six
 </s> add  </s> remove import warnings
 </s> add  </s> remove import sys
 </s> add  </s> remove from django.utils._os import upath
 </s> add 
  import copy


  from django.db.backends.schema import BaseDatabaseSchemaEditor
  from django.db.utils import DatabaseError
  
  
  class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
keep replace replace keep keep keep keep keep
 Fixed a number of flake8 errors -- particularly around unused imports and local variables 
django/db/backends/oracle/schema.py