How to parse "difficult" field in LMDB?

[soyebn]

I added the following code in def get_bounding_box(stream): after parsing code of reading bbox. But I always get is_difficult as 48. Any help on what am I doing wrong. I am assuming difficult follows immediately after bbox coordinates.

stream.seek(to_next_flt, 1)
ymax = struct.unpack('f', stream.read(4))[0]

is_difficult = struct.unpack('H', stream.read(2))[0]
to_end = 0