Is it possible to run a Python method from a Flutter app?
No, there's no provided way to call directly into Python code from Dart, and by extension Flutter.
If this is absolutely critical to your application, you could theoretically call into a Python method from Java/Kotlin on Android using the approach described here and then pass the result back to Dart code via a MethodChannel. However, you're probably better off finding a Flutter plugin or Dart package that can do the work you need to perform.