Filter _xpython-prefixed variables

schema/main.json

@@ -38,6 +38,9 @@
         "xpython": [
           "display",
           "ptvsd",
+          "_xpython_get_connection_filename",
+          "_xpython_launch",
+          "_pydev_stop_at_break",
           "__annotations__",
           "__builtins__",
           "__doc__",