Function verify 

pub fn verify(
    a: &UnitView<'_>,
    b: &UnitView<'_>,
    config: &VerifyConfig,
) -> Verdict

Verify a candidate pair, producing its similarity breakdown, alignment and clone classification.

The verdict is a property of the pair, not of the order the two units were passed in: several alignments can be equally long, and which one the recurrence settles on depends on which unit leads, so the same two units would otherwise score differently depending on which of them a group picked as its medoid. The pair is therefore ordered by content before measuring, and the alignment is mirrored back so the caller still reads it as (a, b).