improve python script error messages

frontend/wailsjs/go/backend_golang/App.d.ts

@@ -22,6 +22,8 @@ export function FileExists(arg1:string):Promise<boolean>;
 
 export function GetPlatform():Promise<string>;
 
+export function GetPyError():Promise<string>;
+
 export function InstallPyDep(arg1:string,arg2:boolean):Promise<string>;
 
 export function ListDirFiles(arg1:string):Promise<Array<backend_golang.FileInfo>>;

frontend/wailsjs/go/backend_golang/App.js

@@ -42,6 +42,10 @@ export function GetPlatform() {
   return window['go']['backend_golang']['App']['GetPlatform']();
 }
 
+export function GetPyError() {
+  return window['go']['backend_golang']['App']['GetPyError']();
+}
+
 export function InstallPyDep(arg1, arg2) {
   return window['go']['backend_golang']['App']['InstallPyDep'](arg1, arg2);
 }