Dictionary is a marisa_trie.BytesTrie. It maps words as they are written (without stress marks) to one or more possible stress positions along with morphological info that helps to resolve ambiguity.
Key is a word without any stress marks (let's call it base).
Value is a byte string in one of the following formats.
Value format #1: Base word has only one possible accent position.
In this case, each byte in the value is a character position of a stressed vowels. Most often, there will be only one, but more is also possible. Example: b'\x02' means that the accent placed on the character with index 2.
Value format #2: Base word has multiple possible accent positions.
The format in this case is
b'{entry_1}{entry_2}...{entry_N}'
where each entry is
b'{pos}\xFE{compressed_tags}\xFF'
compressed_tags is a sequence of bytes, where each byte corresponds to
a morphological or POS tag (see ukrainian_word_stress.tags.TAGS)
0xFE and 0xFF are one byte separators.