Test for Usable Characters

[Iainrach]

Adafruit_framebuf.py on Line 567 line = struct.unpack("B", self._font.read(1))[0] randomly causing
struct.error: ('unpack requires a buffer of 1 byte')

from my code

LineBuf =(x.text.strip()[0:60])
pixel_framebuf.text(LineBuf, i, 4, 0x0000FF)

It appears the web text randomly contained Unicode Decimal 8217 RIGHT SINGLE QUOTATION MARK which I'm guessing is not part of font5x8.bin and thus generates the error? When I replace with Unicode Decimal 39 APOSTROPHE all is good.

Of course they look pretty identical so it was difficult to understand the problem.

Is it possible to include a check for Usable Characters ?