How do I trigger QTextEdit.inputMethodEvent() for keyboard events?

I have created the backend code for my keyboard driver. The driver will take roman characters as input and output Tibetan Unicode.
I would like to embed this driver in my application and I am currently trying to understand the best way to achieve this.

I know I could hack together something where I handle events for every single character that might be inputted, but this seems like a really ugly hack where I'm trying to poorly reinvent functionality that seems to already be available in Qt, namely through QInputMethodEvent, since it seems to handle intermediate states where a partially typed string will not yield valid output from my driver.

I have subclassed QTextEdit, called the object's .setAttribute(Qt.WA_InputMethodEnabled) and tried to implement inputMethodEvent() and see if this event is triggered by keypresses, but inputMethodEvent() isn't called at all.

I found that there's also QInputContext, which can send a QInputMethodEvent, but since I'm not very familiar with Qt yet and trying to learn by doing this, I'm not sure how I utilize QInputContext.

Basically I would like to be able to do the following:

1. Intercept keyboard events and pass them to a buffer
2. Process the buffer with my driver.
   
   a. Represent intermediate states in the QTextEdit widget.
   b. Replace the intermediate output in the QTextEdit widget with the completed Tibetan Unicode word

I am completely lost, so any help whatsoever would be of tremendous benefit. Just knowing how to trigger the inputMethodEvent() would be a great start.

Thank you.