I was trying to write an extension for Idle, and was noticing extension keys defined in ~/.idlerc weren't being used, so I looked into it and found that in idlelib.config.idleConf, `GetExtensionKeys`, `__GetRawExtensionKeys`, and `GetKeyBinding` would never check for user keys, always assuming default keys have everything. This is not always true. In a system with multiple users, you would not want to modify the default config file for a custom extension, as that is used for everyone.