  
  
  class NotAuthenticated(APIException):
      status_code = status.HTTP_401_UNAUTHORIZED
      default_detail = _('Authentication credentials were not provided.')
  
  
  class PermissionDenied(APIException):
      status_code = status.HTTP_403_FORBIDDEN
      default_detail = _('You do not have permission to perform this action.')
 
</s> remove     default_detail = _('You do not have permission to perform this action.')
 </s> add     default_detail = _("You do not have permission to perform this action.") </s> remove     default_detail = _('Incorrect authentication credentials.')
 </s> add     default_detail = _("Incorrect authentication credentials.") </s> remove     default_detail = _('Malformed request.')
 </s> add     default_detail = _("Malformed request.") </s> remove     default_detail = _('Not found.')
 </s> add     default_detail = _("Not found.") </s> remove     default_detail = _("Method {method} not allowed.")
 </s> add     default_detail = _("Method '{method}' not allowed.")
    default_detail = _("Authentication credentials were not provided.")
  
  
  class NotAuthenticated(APIException):
      status_code = status.HTTP_401_UNAUTHORIZED
    default_detail = _("Authentication credentials were not provided.")
  
  
  class PermissionDenied(APIException):
      status_code = status.HTTP_403_FORBIDDEN
      default_detail = _('You do not have permission to perform this action.')
keep keep keep keep replace keep keep keep keep keep
 use double quotes for user visible strings; end user visible strings in full stops; add some missing translation tags 
rest_framework/exceptions.py