An implementation of the Modified UTF-8 encoder and decoder from Java, meant for use within TagForge, an NBT parser and dumper!
import mutf8
assert decodeMutf8([0xE3.byte, 0x81, 0x82]) == "あ"
assert encodeMutf8("Hello☆") == [0x48.byte, 0x65, 0x6c, 0x6c, 0x6f, 0xe2, 0x98, 0x86]