Can extra functions be exposed

It's been a long time since I used C/C++, and I'm pretty new to Python, but I notice that [`inc/microbit/microbitimage.h`](https://github.com/bbcmicrobit/micropython/blob/master/inc/microbit/microbitimage.h#L69) has a function declaration, `microbit_image_for_char`, that sounds like just what I need - could it be exposed as a python function for turning a single character into the LED image string, or maybe a string into an array of LED image strings?

Thanks :)