When you fix the error "error: [Errno 2] No such file or directory: 'src/main/assets/private.mp3'"

Install python-for-android:

```python
pip install git+https://github.com/kivy/python-for-android.git
```

Building the project ends with an error:

```python
error: [Errno 2] No such file or directory: 'src/main/assets/private.mp3'
```

You have this error for a long time. And, despite the fact that you say that you corrected it, it still appears.