Calling a C++ Function From the External Python Script (Seperate Files)

I am working on a project that is mainly written on Python, but the part where the camera captures are being processed is in a QT project (C++).

For ex:
There is a start button in the QT which activates several functions that are written in C++:

in main.qml:

Button {
    id: startbutton
    x: 910
    y: 822
    text: qsTr("Start")

    onPressed: {
        VideoStreamer.startcapturing()
    }
}

For now, I am clicking on this button manually, but I need to write a function that activates this button whenever it is needed in the Python algorithm.

So the Python script should call the start button somehow. Is there a way to call this VideoStreamer.startcapturing() from the python script?

I’ve read about pipes but I couldn’t implement anything, actually I don’t even know whether I should focus on the communication between QT and Python or C++ and Python.

Please explain it through some example codes using the above code piece, not just ideas. Because I’ve already read tons of things but I am too noob to apply them.

Notes:
OS: Ubuntu 18.04.6 LTS

All the projects are in the same PC.