In the app.yaml configuration file of a Python 3 application, "threadsafe" field is deprecated. All applications are presumed to be threadsafe. You may find related details in the "Updating app.yaml" sub-chapter <https://cloud.google.com/appengine/docs/standard/python/migrate-to-python3/config-files#updating_appyaml> of the "Preparing configuration files for the Python 3 runtime" documentation page.
You did not mention what "skip_files:" related errors you are faced with. All this is above the scope of this discussion group, in fact off-topic. You should post such questions to StackOverflow, or other similar forums. This forum is meant for general discussion on the platform and its services. By contrast, in StackOverflow, you get in contact with experienced programmers, who are happy to help. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to google-appengine+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/7b64ca15-1d87-4654-b1d9-90829338dec3%40googlegroups.com.